China Exports by Country
Last Previous European Union 45278100.00 40132200.00 USD THO Feb/20 United States 39831600.00 37218900.00 USD THO Jun/20 Hong Kong 20737200.00 20851700.00 USD THO Jun/20 Japan
10856200.00 13264500.00 USD THO Jun/20 Vietnam 9014600.00 8586400.00 USD THO Jun/20
China Imports By Country
Value Year South Korea $204.57B 2018 Japan
$180.40B
2018
United States $156.00B 2018 China [presumably HK] $146.38B 2018 Germany $106.26B 2018
Australia $105.08B 2018
https://tradingeconomics.com/china/imports-by-country
Looks like it's a balanced trade currently. See above.
Have you seen the WHO report already. Here's me thinking they only just set up an investigation team. Do you have a link to their report?Originally Posted by katie23;4 136794
They also form joint companies with foreign companies, which are considered amenable to both.
You may wish to update your knowledge regarding the worlds car and truck manufacturers who source parts from and have factories in China.
Here is one report:
Automakers in China gradually reopen after virus shutdown
snips:
"Automakers are reopening factories in China that were idled by anti-virus controls as they try to reverse a sales slump in their biggest market.
Local officials have orders from the ruling Communist Party to get businesses functioning again while still enforcing anti-disease curbs that shut down much of the world's second-largest economy.
"Local governments are putting their full weight behind helping businesses open," the president of the American Chamber of Commerce in Shanghai, Ker Gibbs, said in a statement."
"Toyota Motor Co. said two factories reopened Monday with one of the usual two daily shifts working.
Volkswagen AG, Ford Motor Co., Mercedes Benz and Chinese brand Geely resumed some operations last week.
General Motors Co. said a "staggered start" across its factories began Saturday.
Nissan Motor Co. plans to restart this week.
Groupe Renault said one of its factories in the southern city of Guangzhou, near Hong Kong, reopened Monday. "
"UBS estimates China supplies 8% of auto parts exports worldwide."
https://www.cbsnews.com/news/automakers-coronavirus-china-factories-gradually-reopen-after-virus-shutdown/
Or do you believe the world class companies produce sub standard products from Chinese suppliers.
Have you visited any joint venture/foreign manufacturers factories in China?
Here is a list of foreign companies:
Joint ventures
A foreign car manufacturer is allowed at most 2 joint ventures in China.[1]
Foreign Auto Manufacturer Joint Ventures (with) BMW Brilliance Auto (BMW-Brilliance), BAIC (BAIC - BMW) Fiat GAC, BAIC (BAIC FCA Automobile Co. Ltd) Ford Changan FAW General Motors (GM) SAIC, FAW, GAC (GAC Chevrolet Opel Motors Co.Ltd) Honda GAC (Guangqi Honda), Dongfeng Motor Group (Dongfeng Honda) Hyundai BAIC, Great Wall (Great Wall-Hyundai Motors Co.Ltd) Jaguar Land Rover Chery (Chery Jaguar Land Rover) Kia Dongfeng Motor Corporation (Dongfeng Yueda Kia) GAC (GAC Hafei Kia Motors Co Ltd.) Luxgen Dongfeng Motor, Soueast Mazda FAW, Changan Mercedes-Benz BAIC (Beijing-Benz), BYD (Denza) Mitsubishi Soueast, GAC (GAC-Mitsubishi) Nissan Dongfeng Motor Group (Dongfeng Motor Co., Ltd.) , BAIC Group (BAIC Nissan) Peugeot Dongfeng Motor Group, Great.Wall (Great Wall Peugeot Citroën Co. Ltd) Renault Dongfeng Motor Group ,FAW (FAW Renault Nissan Motors Co. Ltd) Suzuki Changan, Dongfeng Motor Group Toyota GAC (GAC-Toyota), FAW Volkswagen SAIC, FAW,GAC Isuzu JMCG, JIM,GAC
https://en.wikipedia.org/wiki/List_o...urers_of_China
Last edited by OhOh; 19-07-2020 at 06:12 PM. Reason: Spelling
A tray full of GOLD is not worth a moment in time.
Which has absolutely sweet f.a. to do with the discussion. You really are incapable of following a thread.
Ok . . .
Albino animals, explained
Albino animals don't have it easy; their whiteness makes them prime targets for predators.
2 MINUTE READ
BY
JANI ACTMAN
Although rare in nature, albino animals have been spotted everywhere from the skies to the seas. These unique creatures have partial or complete loss of pigmentation, hence their pale skin tone compared to other members of their species. Even though the birth of an albino animal is considered a sacred or auspicious event in some cultures, research suggests that some albino animals have difficulty in the wild.
What is albinism?
In mammals, albinism occurs when an individual inherits one or more mutated genes from both parents that interfere with the body’s production of melanin, the main pigment that determines the color of skin, fur, and eyes. The production of melanin occurs within melanocytes, specialized cells that are present but not fully functional in albino mammals.
Non-mammal animals can also be albino, but because they can produce other pigments in addition to melanin, they may not appear fully white. Even albino mammals can show some color if their melanin-making genes haven’t been totally damaged.
It’s important to note that not all white animals are albino. Some animals are simply light-skinned, or they might suffer from other conditions, such as leucism and isabellinism. To tell the difference between an albino animal and one without the disease, look at the eyes: blood vessels normally masked by pigment show through in albino creatures, making their eyes pinkish in color.
Surviving with albinism
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Albino wildlife may face obstacles in nature. They often have poor eyesight, which puts them at a disadvantage when hunting for food and avoiding danger. In some cases they have trouble finding a mate, and their inability to camouflage themselves makes them vulnerable to predators. Take albino alligators, for instance, who make such an obvious target for predators that they’re often eaten before they reach adulthood.
Albino animals and other unusually pale wildlife are also more vulnerable to poachers looking to capitalize on booming demand for exotic pets or products derived from rare creatures. The threat to these animals is so real that a nonprofit bought an island off Indonesia just so that it could build a sanctuary there for an albino orangutan, who will be protected by security guards nonstop when she moves there in June 2019. Many albino animals are also sent to zoos for protection. One of the most well-known albino zoo animals was Snowflake, a gorilla featured in National Geographic magazine who died from skin cancer in 2003.
In addition to poachers, some trophy hunters also favor the rare. Albino deer are so enticing to hunters, for example, that several U.S. states prohibit them from being hunted.
Some albino creatures do find success in the wild, however. In Olney, Illinois, there’s a thriving population of nearly a hundred albino squirrels. The town is so proud of them that it encourages residents to feed them and has passed laws to protect them from being hit by vehicles.
They're not blank, are you even capable of seeing the same things as others?
Oh, they certainly are. Pray tell how albinism in animals isn't factual.
https://www.sciencedirect.com/topics...nt-composition8.2 Foamed Cement Slurries
Foamed cement slurries have included foaming and stabilizing additives which include components such as isopropyl alcohol that interfere with aquatic life. In addition, one or more of the components are often flammable and make the shipment of the foaming and stabilizing additives expensive.
Foamed hydraulic cement slurries which include environmentally benign foaming and stabilizing additives that do not include flammable components have been developed [35].
An environmentally benign additive for foaming and stabilizing a cement slurry is a mixture of an ammonium salt of an alkyl ether sulfate surfactant, a cocoamidopropyl hydroxysultaine surfactant, a cocoamidopropyl dimethylamine oxide surfactant, sodium chloride, and water [35].
8.2.1 Defoaming Agents
Hydraulic cement compositions often comprise defoamers. Defoamers are utilized, as components in well treatment fluids to prevent the formation of foam or the entrainment of gas during the preparation and placement of the well treatment fluid in the subterranean formation [36].
Defoamers also have been utilized for breaking foamed fluids. For example, when an operator desires to dispose of a foamed well treatment fluid aboveground, the operator may add a defoamer to the well treatment fluid to break the foam, and thereby facilitate disposal of the well treatment fluid. Defoamers often are included in cement compositions, in order to ensure a proper mixing and to provide adequate control over the density of the cement composition.
A variety of defoamers are known. However, some of them may have undesirable environmental characteristics or may be limited by strict environmental regulations in certain areas of the world.
Cement compositions with environmentally compatible defoamers have been described [36]. Such environmentally compatible defoamers comprise octanol, hexanol, or butanol and a surfactant.
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Other Water-Based Uses
In Water-Based Chemicals and Technology for Drilling, Completion, and Workover Fluids, 2015
3.6.4 Carboxymethylated Inulin
A cement composition that contains carboxylated inulin, for example, carboxymethylated inulin, overcomes problems such as high temperatures that may result in particle settling [9]. For instance, carboxymethylated inulin provides the cement composition with a very low free water separation. In addition, the carboxymethylated inulin allows the cement composition to maintain its viscosity under increasing wellbore temperatures.
The method of carboxylating inulin consists of the carboxymethylation of inulin with chloroacetate to obtain the carboxymethylated inulin. The synthesis has been detailed [12].
Alternately, the carboxyl groups may be introduced into inulin by oxidation with suitable oxidants to form carboxylated inulin. Such oxidized inulins have been described in the literature [13]. The oxidation is achieved with periodic acid or periodate salts, lead(IV) salts, or permanganate.
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Hydration, Setting and Hardening of Portland Cement
James Beaudoin, Ivan Odler, in Lea's Chemistry of Cement and Concrete (Fifth Edition), 2019
5.7.3 Effect of Cement Composition on Strength
The effect of cement composition on cement strength has been studied extensively.177,182,189,400,420 It appears that this effect is a rather complex one and depends on a variety of factors such as the mutual ratios of clinker minerals, the amount and form of added calcium sulfate and the presence of minor oxides. The available experimental data may be summarised as follows.
•The existing relationship between clinker phase composition and cement strength is typically not a linear one and the strength of cement cannot be considered to be just an additive function of the strengths of the participating clinker minerals.
•All clinker phases contribute to strength development; however, the magnitude of this effect differs for different clinker constituents and depends also on the hydration time.
•The effect of C3S is most pronounced at all ages, whereas the contribution of C2S to strength becomes significant only at longer hydration times. The strength at any hydration time increases with increasing C3S content up to ~ 70% and tends to decline when the content of C3S in clinker is even higher.
•The contributions of C3A and C4AF to strength are relatively small but complex. With increasing content of C3A or C4AF the strength increases only to a certain degree and tends to decline at higher contents. There exists an obvious interaction between C3A and C4AF with regard to their effect on strength.
For narrow ranges of clinker composition and a constant gypsum content and fineness, the existing composition–strength relationship may be expressed with an acceptable accuracy with an equation of the type
(5.21)σ=a0+a1c1+a2c2+a3c3+a4c4
where c1; c2, etc. are the contents of the phases C3S, C2S, etc. in clinker and a0, a, a2 … are constants (regression coefficients) whose magnitude depends also on the hydration time and employed testing method.
Besides the clinker phase composition, the presence of minor oxides may also affect the resultant cement strength. Among these, the effect of alkali oxides K2O and Na2O has been studied most extensively.177,182,400,421–423 Unfortunately, even though a significant effect of alkalis on cement strength has been generally recognised, data on the character and magnitude of this effect are not uniform. Alkalis bound within the crystalline lattice of clinker minerals appear to act differently to those present in the form of soluble sulfates.
The effect of MgO on strength was found not to be very significant.183 Free-lime CaO affects cement strength by inducing unsoundness and by reducing the amount of C3S formed.
Calcium sulfate interground with clinker affects cement strength at all hydration times. With increasing SO3 content the strength tends to increase up to the ‘optimum gypsum’ value and declines at even higher SO3 contents. The exact amount of calcium sulfate that produces highest strength depends on the composition of the clinker, cement fineness, the form of added sulfate and hydration time.183,189,424–426
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Special Cements
John Bensted, in Lea's Chemistry of Cement and Concrete (Fourth Edition), 1998
Ordinary hydration
Oilwell cements are usually based upon Portland cement compositions, which comprise four principal clinker mineral phases: tricalcium silicate (Ca3SiO5), dicalcium silicate (Ca2SiO4), tricalcium aluminate (Ca3Al2O6) and a calcium aluminoferrite of more variable composition (approximately Ca2AlFeO5), to which some calcium sulfate in the form of the dihydrate gypsum (CaSO4·2H2O), or its derivatives like hemihydrate (CaSO4·0.5H2O) or natural anhydrite (CaSO4), have been incorporated during the manufacturing process to regulate thickening behaviour. In situations where sulfate resistance is required, the quantities of tricalcium aluminate must be reduced, because this phase is the most susceptible to sulfate attack.54 The hydration of ordinary and sulfate-resisting Portland cements has been described in various texts.44,45,55 Compressive strength is obtained mainly from the reaction of the silicate phases to form calcium silicate hydrate. Tricalcium silicate is the principal cementing phase, whereas dicalcium silicate (usually in the β form) reacts at a much slower rate to form similar hydration products. Early compressive strength is largely obtained from tricalcium silicate, but at later ages (e.g. 28 days and beyond) the contribution from β-dicalcium silicate becomes very important. None of the principal cementing phases is pure — all contain several per cent of impurities in solid solution, which are derived from the raw materials and the fuel, and may be affected by the manufacturing process. These give rise to hydration products, which again are not pure products and contain impurities in solid solution. The hydraulic behaviour of the cementing phases is influenced by the presence of these impurity ions.
At surface temperatures or just above, the silicates react with water to form an amorphous calcium silicate hydrate, which can be represented approximately as follows:
(14.3)2Ca3SiO5+6H2O→'Ca3Si2O7⋅3H2O'+3Ca(OH)2
(14.4)2Ca2SiO4+4H2O→'Ca3Si2O7⋅3H2O'+Ca(OH)2
The aforementioned reactions are not normal dissolution and precipitation types, but arise topochemically at the clinker silicate surfaces. The equations given above are only approximate, because the calcium silicate hydrate formed, known as C-S-H, is in reality a very poorly crystalline non-stoichiometric material consisting principally of dimeric units at first, but which subsequently slowly polymerise after a few days to give higher linear units like pentamer and thence octamer, and so on, with the passing of time.
The appearance of a hardened MSR Class H oilwell cement hydrated for 4 months at a water/cement ratio of 0.38 is illustrated in Figure 14.3.
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Fig. 14.3. MSR Class H oilwell cement (scale bars 5 μm). (a) Unhydrated, showing clinker particles and rodlets of gypsum, (b) Hydrated at water/cement ratio = 0.38 for 4 months at 27°C, revealing dense formation of C-S-H, hexagonal platelets of calcium hydroxide and ‘monosulfate-C4(A,F)H13’ (AFm phase) plus some rodlets of ettringite (AFt phase).
The hydration products from the tri- and β-dicalcium silicate phases at up to ∼ 100°C do not differ essentially from those formed at ambient temperature. However, there may be some differences in microstructure and morphology. No changes in the mechanism of hydration have been reported in the temperature range from ambient to 90°C, although more polysilicate hydrate in relation to dimer has been found in calcium silicate hydrate pastes at 65°C than at 25°C.56 At elevated temperatures the hydration of β-dicalcium silicate is accelerated in relation to that of tricalcium silicate, which could be related to the higher solubility of silica and lower solubility of calcium hydroxide under these conditions.57
The solubility product and morphology of C-S-H formed in sodium chloride or sodium hydroxide solution are not very different from those of C-S-H produced in water. Na+ ions are incorporated in the C-S-H gel. This C-S-H easily reverts to the normal C-S-H after dispersing in water.58
The tricalcium aluminate and calcium aluminoferrite phases react with the added calcium sulfate to form ettringite, the rate of the former reaction being faster than that of the latter:
(14.5)Ca3Al2O6+3{CaSO4⋅2H2O}+26H2O→Ca6[Al(OH)6]2(SO4)3⋅26H2O
(14.6)Ca2AlFeO5+Ca(OH)2+3{CaSO4⋅2H2O}+25H2O→Ca6[Al0.5Fe0.5(OH)6]2(SO4)3⋅26H2O
In practice only one form of ettringite is produced, since the effects of solid solution between ettringite derived from the aluminate and ettringite derived from the aluminoferrite plus their containing impurities from the parent clinker phases means that there is just one continuous mass of ettringite being formed. The parent phases in respect of ettringite formation at best make only secondary contributions to thickening and the development of compressive strength.32,36 Only very small quantities (sometimes none) of tricalcium aluminate are normally present in the API HSR cements of Classes B—H, where most (if not all) the ettringite arises from the aluminoferrite phase; this reaction is somewhat slower than that of tricalcium aluminate and also requires the presence of calcium hydroxide to react. When the gypsum is effectively used up, commonly after several hours, ettringite changes to the monosulfoaluminate hydrate Ca4[(Al,Fe)(OH)6]2SO4·6H2O which readily enters into solid solution with the calcium aluminate hydrate Ca2(Al,Fe)(OH)7·3H2O formed at this stage from aluminate and aluminoferrite reacting with water.46
Some calcium hydroxide is present at the beginning of hydration, where the aqueous phase of the cement slurry can be considered for simplicity as essentially a limewater medium, being derived from some hydration of the small free lime content:
(14.7)CaO+H2O→Ca(OH)2
Alkalis are present in oilwell cements in small quantities, both in the form of alkali sulfates and incorporated in the main clinker phases. They exist potentially as sulfates if sufficient SO3 is present in the clinker, and the preferred sulfate form is potassium sulfate (K2SO4). A series of double alkali sulfates can also exist, namely calcium langbeinite [K2Ca2(SO4)3] and potassium sodium sulfate [(K,Na)2SO4]. The alkali metal ions from the sulfates readily enter solution when the cement is mixed with water and accelerate the early hydration reactions, particularly those of tricalcium silicate and tricalcium aluminate. Limits of 0.75 per cent equivalent Na2O are included in API Specification 10A for Class G and H cements to permit adequate thickening times to be achieved downhole.
Some free magnesium oxide (MgO) may be encountered with high magnesia-containing oilwell cements. This hydrates slowly to the hydroxide:
(14.8)MgO+H2O→Mg(OH)2
which may crystallise as brucite. Its effects on oilwell cement properties are similar to those of free lime.
Class C cement is a rapid-hardening Portland cement (ASTM Type III) and its early hydration chemistry is accelerated. For this reason a higher water/cement ratio of 0.56 is permitted for achieving a suitable thickening time and higher early compressive strength development. The retarded cements of Classes D, E and F take longer to achieve thickening by virtue of their lower rate of hydration of tricalcium silicate. Class H cement is coarser than Class G from the same source and ordinarily will hydrate at a slower rate, since the rates of clinker phase reactions decrease with coarser surface areas. Class H cement is designed for use at lower water/cement ratios than Class G cement, such as 0.38 specified in API Specification 10A for achieving suitable thickening and compressive strength, although in practice it is often used at much higher water levels (e.g. 46 per cent) in cementing formulations. Likewise, Class G cement is also often employed in cementing formulations at water levels different from the 44 per cent by weight of cement specified.
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Special Cements
Martin Liska, ... John Bensted, in Lea's Chemistry of Cement and Concrete (Fifth Edition), 2019
13.2.8.1 Ordinary Hydration
Oil-well cements are usually based upon Portland cement compositions, which comprise four principal clinker mineral phases: tricalcium silicate (Ca3SiO5), dicalcium silicate (Ca2SiO4), tricalcium aluminate (Ca3Al2O6) and a calcium aluminoferrite of more variable composition (approximately Ca2AlFeO5), to which some calcium sulfate in the form of the dihydrate gypsum (CaSO4 2H2O), or its derivatives like hemihydrate (CaSO4 0.5H2O) or natural anhydrite (CaSO4), have been incorporated during the manufacturing process to regulate thickening behaviour. In situations where sulfate resistance is required, the quantities of tricalcium aluminate must be reduced, because this phase is the most susceptible to sulfate attack.58 The hydration of ordinary and sulfate-resisting Portland cements has been described in various texts.47,48,59 Compressive strength is obtained mainly from the reaction of the silicate phases to form calcium silicate hydrate. Tricalcium silicate is the principal cementing phase, whereas dicalcium silicate (usually in the β form) reacts at a much slower rate to form similar hydration products. Early compressive strength is largely obtained from tricalcium silicate, but at later ages (e.g. 28 days and beyond) the contribution from β-dicalcium silicate becomes very important. None of the principal cementing phases is pure—all contain several per cent of impurities in solid solution, which are derived from the raw materials and the fuel, and may be affected by the manufacturing process. These give rise to hydration products, which again are not pure products and contain impurities in solid solution. The hydraulic behaviour of the cementing phases is influenced by the presence of these impurity ions.
At surface temperatures or just above, the silicates react with water to form an amorphous calcium silicate hydrate, which can be represented approximately as follows:
(13.3)2Ca3SiO5+6H2O→Ca3Si2O7⋅3H2O+3CaOH2
(13.4)2Ca2SiO4+4H2O→Ca3Si2O7⋅3H2O+CaOH2
The aforementioned reactions are not normal dissolution and precipitation types, but arise topochemically at the clinker silicate surfaces. The equations given above are only approximate, because the calcium silicate hydrate formed, known as C-S-H, is in reality a very poorly crystalline non-stoichiometric material consisting principally of dimeric units at first, but which subsequently slowly polymerise after a few days to give higher linear units like pentamer and thence octamer, and so on, with the passing of time.
The appearance of a hardened MSR Class H oil-well cement hydrated for 4months at a water/cement ratio of 0.38 is illustrated in Fig. 13.3.
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Fig. 13.3. MSR class H oil-well cement (scale bars 5 μm). (A) Unhydrated, showing clinker particles and rodlets of gypsum, (B) hydrated at water/cement ratio = 0.38 for 4 months at 27°C, revealing dense formation of C-S-H, hexagonal platelets of calcium hydroxide and ‘monosulfate-C4(A,F)H13’ (AFm phase) plus some rodlets of ettringite (AFt phase).
The hydration products from the tri- and β-dicalcium silicate phases at up to ~ 100°C do not differ essentially from those formed at ambient temperature. However, there may be some differences in microstructure and morphology. No changes in the mechanism of hydration have been reported in the temperature range from ambient to 90°C, although more polysilicate hydrate in relation to dimer has been found in calcium silicate hydrate pastes at 65°C than at 25°C.60 At elevated temperatures the hydration of β-dicalcium silicate is accelerated in relation to that of tricalcium silicate, which could be related to the higher solubility of silica and lower solubility of calcium hydroxide under these conditions.61
The solubility product and morphology of C-S-H formed in sodium chloride or sodium hydroxide solution are not very different from those of C-S-H produced in water. Na+ ions are incorporated in the C-S-H gel. This C-S-H easily reverts to the normal C-S-H after dispersing in water.62
The tricalcium aluminate and calcium aluminoferrite phases react with the added calcium sulfate to form ettringite, the rate of the former reaction being faster than that of the latter:
(13.5)Ca3Al2O6+3CaSO4⋅2H2O+26H2O→Ca6AlOH62SO43⋅26H2O
(13.6)Ca3AlFeO5+CaOH2+3CaSO4⋅2H2O+25H2O→Ca6Al0.5Fe0.5OH62SO43⋅26H2O
In practice only one form of ettringite is produced, since the effects of solid solution between ettringite derived from the aluminate and ettringite derived from the aluminoferrite plus their containing impurities from the parent clinker phases means that there is just one continuous mass of ettringite being formed. The parent phases in respect of ettringite formation at best make only secondary contributions to thickening and the development of compressive strength.33,37 Only very small quantities (sometimes none) of tricalcium aluminate are normally present in the API HSR cements of Classes B–H, where most (if not all) the ettringite arises from the aluminoferrite phase; this reaction is somewhat slower than that of tricalcium aluminate and also requires the presence of calcium hydroxide to react. When the gypsum is effectively used up, commonly after several hours, ettringite changes to the monosulfoaluminate hydrate Ca4[(Al,Fe)(OH)6]2SO4 6H2O which readily enters into solid solution with the calcium aluminate hydrate Ca2(Al,Fe)(OH)7 3H2O formed at this stage from aluminate and aluminoferrite reacting with water.49
Some calcium hydroxide is present at the beginning of hydration, where the aqueous phase of the cement slurry can be considered for simplicity as essentially a limewater medium, being derived from some hydration of the small free lime content:
(13.7)CaO+H2O→CaOH2
Alkalis are present in oil-well cements in small quantities, both in the form of alkali sulfates and incorporated in the main clinker phases. They exist potentially as sulfates if sufficient SO3 is present in the clinker, and the preferred sulfate form is potassium sulfate (K2SO4). A series of double alkali sulfates can also exist, namely, calcium langbeinite [K2Ca2(SO4)3] and potassium sodium sulfate [(K,Na)2SO4]. The alkali metal ions from the sulfates readily enter solution when the cement is mixed with water and accelerate the early hydration reactions, particularly those of tricalcium silicate and tricalcium aluminate. Limits of 0.75% equivalent Na2O are included in API Specification 10A for Class G and H cements to permit adequate thickening times to be achieved downhole.
Some free magnesium oxide (MgO) may be encountered with high magnesia-containing oil-well cements. This hydrates slowly to the hydroxide:
(13.8)MgO+H2O→MgOH2
which may crystallise as brucite. Its effects on oil-well cement properties are similar to those of free lime.
Class C cement is a rapid-hardening Portland cement (ASTM Type III) and its early hydration chemistry is accelerated. For this reason a higher water/cement ratio of 0.56 is permitted for achieving a suitable thickening time and higher early compressive strength development. The retarded cements of Classes D, E and F take longer to achieve thickening by virtue of their lower rate of hydration of tricalcium silicate. Class H cement is coarser than Class G from the same source and ordinarily will hydrate at a slower rate, since the rates of clinker phase reactions decrease with coarser surface areas. Class H cement is designed for use at lower water/cement ratios than Class G cement, such as 0.38 specified in API Specification 10A for achieving suitable thickening and compressive strength, although in practice it is often used at much higher water levels (e.g. 46%) in cementing formulations. Likewise, Class G cement is also often employed in cementing formulations at water levels different from the 44% by weight of cement specified.
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Russia: experience of radioactive waste (RAW) management and contaminated site clean-up
A.I. Sobolev, ... O.A. Gorbunova, in Radioactive Waste Management and Contaminated Site Clean-Up, 2013
10.3.2 Restoration of the historical repositories
The main advantage offered by RAW storage is the guaranteed security afforded by the integrity of each separate element of the multi-barrier complex. If any one of these multiple shielding barriers is damaged, the potential risk of migration of radionuclides into the environment increases. Any number of factors can disrupt the integrity of the construction material of the repository and/or of the massif of solidified RAW, principally: (1) the deformation of structural elements as a result of significant temperature variations in the environment (e.g., seasonal freezing and thawing) or as a result of shrinkage; (2) the decompression of seams; and (3) any construction defects including where the different elements meet, such as joints between sides of walls and partitions and the upper overlap. In addition, cracks and microcracks can appear on the surface of the construction (the outer duct), which may be connected to each other, leading to the formation of a system of interconnected channels in the walls of the repositories.
An estimation of the conditions of the man-made barriers, carried out in the early 2000s [6, 7], included comprehensive geological, hydrogeological, geophysical and radiometric studies of the condition of the RAW massif, the soils forming the edge zone and the massif of the surrounding rocks. In the selected zones boreholes 8 m in depth were drilled, and various measurements were taken: the layer-by-layer permeability of the medium was measured; gamma- and thermo-logging were carried out; and the core material (RAW cement compound and soils, as shown in Fig. 10.2) and water was sampled for further radiochemical, chemical, physical, mechanical, micro-structural and microbiological analysis.
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10.2. (a–c) Sampling of cemented RAW from the near-surface repositories.
These comprehensive studies, carried out with the help of boreholes drilled in the near-contour zone, determined that the high sorption property loams of the near-contour zone are indeed a reliable obstacle that prohibits the radionuclides from entering the adjacent massif [8]. During the investigation of the cement compound samples containing RAW (core material), it was established that a cement matrix that has been age-hardened for more than 40 years generally preserves its basic immobilization properties. The majority of samples tested (Table 10.3) have a compressive strength higher than the normative value of 5 MPa [9] and the rate of radionuclide 137Cs leaching is lower than the required level of 1 × 10−3 g/(m2-day). However, sufficient humidity and porosity together with structure friability and low compressive strength attested in several samples from different depths were also observed, showing that destructive processes were taking place in the cement matrix [10].
Master of Ignorance does not disappoint...
CHINA LOST 14 MILLION PEOPLE IN WORLD WAR II. WHY IS THIS FORGOTTEN?
When looking back at World War II, the victors see their own military contributions the clearest. Hence the United Kingdom spotlights the Battle of Britain and El Alamein, the Russians Stalingrad and Kursk, and the Americans D-Day and Midway. The contribution of China, whose war was the longest and among the bloodiest, tends to be forgotten in the West, and for years was little commemorated even in China.
China Lost 14 Million People in World War II. Why Is This Forgotten? - Pacific Standard
Forgotten ally? China's unsung role in World War II
1 Sep 2015
(CNN)On Thursday, there will be a major parade in the heart of Beijing, commemorating the 70th anniversary of the end of World War II in Asia.
In the West, many will see the military hardware and the troops that will, no doubt, be at the center of the event.
But relatively few will remember a historical fact that underpins the ceremony: China was the first country to enter what would become the Second World War, and it was the ally of the United States and the British empire from just after Pearl Harbor in 1941, to the Japanese surrender in 1945.
Yet today, China's memory of the war is becoming more, not less, important, as we move further away from it.
And many in China are becoming resentful that the West fails to remember that China was itself a significant player in the eventual Allied victory.
Forgotten ally? China's unsung role in World War II - CNN
It's about the legacy of Chinese people, not the Chinese state.
Similarly, the Russians did not win the war, did they? Obviously not, as this year White House statement to V-Day has not mentioned the Russians (strangely, my link to that WH statement few weeks ago was here deleted...)
...If the Japs move supply chains to the home islands, they'll have to bring in more imported labor for the menial tasks or increase robot/tech efficiency to an unprecedented degree...
This is a good move. Economic demolition is the real key to defeating the spectre of China as an authoritarian superpower.
They need to have the plug pulled on their gravy train and the renminbi rug ripped from under their feet.
China being substantially impoverished is worth any cost, even if it means impoverishing ourselves and everyone else. As long as China cops it the worst.
And your usual response type:
Nothing to address my question and your first statement, just the usual Klondyke-shit . . . and when you're called out on it:
Typical Klondyke . . . no substance, all obfuscation
...since the Japs tend to regard most non-Japs as inferior, the importation of even more foreign labor may be problematic: ghettos tend to form where folks are sniffed at...SEA looks like a better choice for establishing Jap supply chains: nearby, plenty of cheap labor, malleable governments and easily bribable officials in the event of difficulties...
Majestically enthroned amid the vulgar herd
There are already over 2 million foreign workers in Japan and quite there's a trend in following the path to citizenship. I have a Malaysian Chinese friend who works for a Japanese company in Singapore, worked for them in Japan for years beforehand. He has recently taken up Japanese citizenship. Japan knows it has a demographic problem and is slowly . . . very slowly . . . addressing it
One hope the foreign attacks on China take into account the human rights to the affected Chines citizens.
The business owners/share holders are the targets, local or foreign. They decide where and when to invest their resources. But as we have seen, historically they invest where they can improve their rewards. Disregarding environmental, social or legal safeguards.
Last edited by OhOh; 20-07-2020 at 11:24 AM.
One may adopt the western way, yes?
Destroying countries, starving it's men, woman and children, illegal sanctions, awarding Caribbean holidays to the select few (with a choice of islands depending on category), illegally invading countries ......
They are accepted as normal by some, "because they're worth it".
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