A numerical study is presented,using a homogenization technique to consider the plain strain problem of visco-plastic porous medium shaped by regularly distributed circular particles. Based on a rigid plastic material...A numerical study is presented,using a homogenization technique to consider the plain strain problem of visco-plastic porous medium shaped by regularly distributed circular particles. Based on a rigid plastic material,the paper derives the macroscopic constitutive laws for homogenous equivalent medium. By changing the shape parameter of circular particles,the effect of pore shape on macroscopic constitutive laws is explored. Yield surfaces with different pore shapes are obtained. About voids,a two-scale conception is introduced,which regards main void as macroscopic scale and secondary cavities as microscopic scale. The macroscopic potential involving main and secondary voids is achieved. The proposed macroscopic constitutive law taking microscopic features as influence factors is helpful for exploring the macroscopic mechanical properties of porous medium when numerical simulation is required.展开更多
An article entitled "Highly Effective Layout of Water Resources Is the Key Link in Promoting the Sustainable Development of the Regional Economy in Four Provinces (or Autonomous Regions) of the Chinese Northwest,...An article entitled "Highly Effective Layout of Water Resources Is the Key Link in Promoting the Sustainable Development of the Regional Economy in Four Provinces (or Autonomous Regions) of the Chinese Northwest," contributed by Prof.Huo Mingyuan and carried in the Bulletin’s No.4,1995 issue(Chinese edition),makes an incisive argument and proposes a 24-word guideline emphasizing water-saving in a short period of time and water diversion for long-term operation.All of these viewpoints are correct.展开更多
Nanometer perovskite LaMnO 3+λ, La 0.6Ce 0.4MnO 3+λ and La 0.6Sr 0.4MnO 3+λ were prepared by citric acid-aid ed sol-gel method. The effects of Ce, Sr on the structure and properties of nan ome...Nanometer perovskite LaMnO 3+λ, La 0.6Ce 0.4MnO 3+λ and La 0.6Sr 0.4MnO 3+λ were prepared by citric acid-aid ed sol-gel method. The effects of Ce, Sr on the structure and properties of nan ometer perovskite were studied through DT-TGA, XRD, TEM and BET analyses. The r esults show that, by sol-gel method, LaMnO 3+λ, La 0.6Ce 0. 4MnO 3+λ and La 0.6Sr 0.4MnO 3+λ were made with average particle size of about 60, 100 and 30 nm, respectively. After partially substituting Sr on La positions in LaMnO 3+λ, it is found that Sr is l ocated at the perovskite lattice so as to reduce the formation temperature of th e perovskite. As a result, the perovskite has a smaller particle size and larger specific surface area. On the contrary, it is difficult for Ce to enter the per ovskite lattice. Ce exists mostly in the form of CeO 2 as partially substitutin g La in LaMnO 3+λ. The formation temperature of the perovskite increas es, and the catalyst containing CeO 2 presents a larger particle size and less specific surface area.展开更多
The Whaling in the Antarctic Case (Australia v. Japan: New Zealand intervening) decided by the International Court of Justice (hereinafter "ICJ" or "the Court") on 31 March 2014 dealt with the inte...The Whaling in the Antarctic Case (Australia v. Japan: New Zealand intervening) decided by the International Court of Justice (hereinafter "ICJ" or "the Court") on 31 March 2014 dealt with the interpretation of specific provisions of the 1946 International Convention for the Regulation of Whaling (ICRW), in particular Article VIII.1, and its complementary instruments, i.e., the Schedule and the Annexes of the International Whaling Commission Scientific Committee. The decision of the Court was a remarkable good one. However, its rigorous reasoning focused almost exclusively on the required purpose of "scientific research" of the JARPA II Programme1 permits as set out in the ICRW, approaching the convention as an autonomous self-contained regime which leaves aside other additional grounds. Nonetheless, it would be beneficial for further jurisdictional developments to strengthen the scope of the ICWR system with the applicable provisions of the United Nations Convention on the Law of the Sea (UNCLOS) and other treaties and institutions impinging on whales and whaling, e.g., CITES, Bonn Convention, Antarctic Treaty System, among others. The query remains concerning the unexplored sources of international law ruling Antarctic spaces and species which are absent in the judgment of the Court but may allow an evolutive interpretation of the ICRW.展开更多
基金Sponsored by the National Natural Science Foundation of China(Grant No.10972162)
文摘A numerical study is presented,using a homogenization technique to consider the plain strain problem of visco-plastic porous medium shaped by regularly distributed circular particles. Based on a rigid plastic material,the paper derives the macroscopic constitutive laws for homogenous equivalent medium. By changing the shape parameter of circular particles,the effect of pore shape on macroscopic constitutive laws is explored. Yield surfaces with different pore shapes are obtained. About voids,a two-scale conception is introduced,which regards main void as macroscopic scale and secondary cavities as microscopic scale. The macroscopic potential involving main and secondary voids is achieved. The proposed macroscopic constitutive law taking microscopic features as influence factors is helpful for exploring the macroscopic mechanical properties of porous medium when numerical simulation is required.
文摘An article entitled "Highly Effective Layout of Water Resources Is the Key Link in Promoting the Sustainable Development of the Regional Economy in Four Provinces (or Autonomous Regions) of the Chinese Northwest," contributed by Prof.Huo Mingyuan and carried in the Bulletin’s No.4,1995 issue(Chinese edition),makes an incisive argument and proposes a 24-word guideline emphasizing water-saving in a short period of time and water diversion for long-term operation.All of these viewpoints are correct.
文摘Nanometer perovskite LaMnO 3+λ, La 0.6Ce 0.4MnO 3+λ and La 0.6Sr 0.4MnO 3+λ were prepared by citric acid-aid ed sol-gel method. The effects of Ce, Sr on the structure and properties of nan ometer perovskite were studied through DT-TGA, XRD, TEM and BET analyses. The r esults show that, by sol-gel method, LaMnO 3+λ, La 0.6Ce 0. 4MnO 3+λ and La 0.6Sr 0.4MnO 3+λ were made with average particle size of about 60, 100 and 30 nm, respectively. After partially substituting Sr on La positions in LaMnO 3+λ, it is found that Sr is l ocated at the perovskite lattice so as to reduce the formation temperature of th e perovskite. As a result, the perovskite has a smaller particle size and larger specific surface area. On the contrary, it is difficult for Ce to enter the per ovskite lattice. Ce exists mostly in the form of CeO 2 as partially substitutin g La in LaMnO 3+λ. The formation temperature of the perovskite increas es, and the catalyst containing CeO 2 presents a larger particle size and less specific surface area.
文摘The Whaling in the Antarctic Case (Australia v. Japan: New Zealand intervening) decided by the International Court of Justice (hereinafter "ICJ" or "the Court") on 31 March 2014 dealt with the interpretation of specific provisions of the 1946 International Convention for the Regulation of Whaling (ICRW), in particular Article VIII.1, and its complementary instruments, i.e., the Schedule and the Annexes of the International Whaling Commission Scientific Committee. The decision of the Court was a remarkable good one. However, its rigorous reasoning focused almost exclusively on the required purpose of "scientific research" of the JARPA II Programme1 permits as set out in the ICRW, approaching the convention as an autonomous self-contained regime which leaves aside other additional grounds. Nonetheless, it would be beneficial for further jurisdictional developments to strengthen the scope of the ICWR system with the applicable provisions of the United Nations Convention on the Law of the Sea (UNCLOS) and other treaties and institutions impinging on whales and whaling, e.g., CITES, Bonn Convention, Antarctic Treaty System, among others. The query remains concerning the unexplored sources of international law ruling Antarctic spaces and species which are absent in the judgment of the Court but may allow an evolutive interpretation of the ICRW.
