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Chinese Science Bulletin 1981年第3期26卷 207-212页

作者：蒲富恪李伯臧 Institute of Physics Academia Sinica {0. for any value of H_x and any size of D the saturation state or signle-domain state u=0 and γ=1

We assume that in general D is an ellipsoid （including sphere, infinite elliptic cylinder and infinite plane sheet as particular cases）, h is homogeneous and [（?）g/（?）a]γ=1—hx[k]—hx=[（?）g/（?）β]γ=1—hy[k... 详细信息

关键词： saturation infinite cylinder elliptic ellipsoid magnetization neighborhood assume sheet reversal

Structures that should be Described in higher-Symmetry, Centrosymmetric Space Groups. Part 1. The Disordered Structures of [(Ch_3Ch_2)_4N]_3{[(SCh_2Ch_2S)MoS_3]_2Fe}, [(Ch_3Ch_2)_4N]_2{[S_2CN(C_2h_5)_2]_4Fe_4S_4} and [(Ch_3Ch_2)_4N]_3{[(SCh_2C

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Chinese Journal of Structural Chemistry 2000年第6期19卷 405-410页

作者： Weng NgSeik hu Shengzhi University of Malaya 50 6 0 3 厦门大学福建厦门 36 1 0 0 5

1　ＩＮＴＲＯＤＵＣＴＩＯＮＡｍｅｔｈｏｄｏｆｓｐａｃｅｇｒｏｕｐｒｅｖｉｓｉｏｎｂｙｗｈｉｃｈｔｈｅｓｔｒｕｃｔｕｒｅｆａｃｔｏｒｓｏｆｔｈｅｌｏｗｅｒｓｙｍｍｅｔｒｙｓｔｒｕｃｔｕｒｅａｒｅｇｅｎｅｒａｔｅｄａｎ... 详细信息

1　ＩＮＴＲＯＤＵＣＴＩＯＮＡｍｅｔｈｏｄｏｆｓｐａｃｅｇｒｏｕｐｒｅｖｉｓｉｏｎｂｙｗｈｉｃｈｔｈｅｓｔｒｕｃｔｕｒｅｆａｃｔｏｒｓｏｆｔｈｅｌｏｗｅｒｓｙｍｍｅｔｒｙｓｔｒｕｃｔｕｒｅａｒｅｇｅｎｅｒａｔｅｄａｎｄｔｈｅｓｔｒｕｃｔｕｒｅｉｓｔｈｅｎｓｏｌｖｅｄｆｒｏｍｔｈｅｓｉｍｕｌａｔｅｄｉｎｔｅｎｓｉｔｙｄａｔａｈａｓｂｅｅｎｒｅｃｅｎｔｌｙｒｅｐｏｒｔｅｄ[1].Ｔｈｉｓｍｅｔｈｏｄｉｓｎｏｗａｐｐｌｉｅｄｔｏｔｈｅｒｅｖｉｓｉｏｎｏｆｔｈｅｓｐａｃｅｇｒｏｕｐｏｆｔｈｅｍｅｔａｌｃｌｕｓｔｅｒｃｏｍｐｌｅｘ ,[(ＣＨ3ＣＨ2 ) 4 Ｎ ] 3{[(ＳＣＨ2 ＣＨ2 Ｓ)ＭｏＳ3] 2 Ｆｅ},ｗｈｉｃｈｃｒｙｓｔａｌｌｉｚｅｓｉｎｔｈｅａｃｅｎｔｒｉｃｓｐａｃｅｇｒｏｕｐＣｃ (ａ =1 4.0.0.3(6) ,ｂ =1 8.397( 7) ,ｃ =1 7.571 ( 6) ,β =90..4 6( 3)°;Ｚ =4 ) .ＴｈｅｓｔｒｕｃｔｕｒｅｗａｓｒｅｆｉｎｅｄｔｏＲ =0..0.52 ;ｈｏｗｅｖｅｒ,ａｔｗｏｆｏｌｄａｘｉｓｐａｓｓｉｎｇｔｈｒｏｕｇｈｔｈｅｍｅｔａｌ ...

关键词： SCh2Ch2S)MoS3 Ch3Ch2 C2h5 S2CN Structures of Fe

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Crystal Structures of Two New Monoprotonated Products of 1,4,7 trimethyl-1,4,7-triazacyclononane: （Me3〔9〕aneN3h）(SO3CF3) and （Me3〔9〕aneN3h）I

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Chinese Journal of Structural Chemistry 2000年第1期19卷 48-52页

作者： DENG Dao Lia * ZhANG yan hui a DAI Cong yun a ZENG hong a yAN Zhi Qing a yE Chang Qing a Ronald ha\|Ge ba (Unilever Research SIOC, 354 Fenglin Road, Shanghai 20.0.2. China) b (Unilever Research Laboratorium, Olivier van Noor Unilever Research SIOC 上海 2 0 0 0 32 Unilever Research Laboratorium 荷兰 Vlaardinge

Two new monoprotonated products of macrocyclic polyamine 1,4,7 trimethyl 1,4,7 triazacyclononane(Me 3〔9〕aneN 3), (Me 3〔9〕aneN 3h)(SO 3CF 3) 1 (C 10.h 22 N 3O 3SF 3, M r =321.36) and (Me 3〔9〕aneN 3h)I 2 (C 9h 22 N 3I, M r =299.20. were obtained by the reactions of Me 3〔9〕aneN 3 and yttrium triflate or ytterbium diiodide as the unexpected products. The crystal structures of compounds 1 and 2 have been determined. Crystal 1 is orthorhombic, space group P2 12 12 1(#19), a =12.60.(3), b=13.531(1), c=9.225(3) , V=1573.9(7)  3, Z=4, D c= 1.356 g/cm 3, μ =2.47 cm -1 , F (0.0.=680.and R=0.0.2, R w =0.0.2 for 80. unique reflections with I>2σ(I) . Crystal 2 belongs to the orthorhombic system with space group P2 12 12 1(#19), a=11.417(2), b=13.0.9(3), c=8.762(2) , V=1310.5(4)  3, Z=4, D c =1\^516 g/cm 3, μ =24.14 cm -1 , F (0.0.=60. and R=0.0.5, R w =0.0.2 for 1427 unique reflections with I>3σ(I) . The two structures contain the same cyclic framework in which the acid proton is bonded to an amine nitrogen. This proton exhibits strong intramolecular hydrogen bonds with the other two nitrogen atoms. The methyl groups are directed away from the ring cavity. The bond distance between acid proton and an amine nitrogen in compound 2 is extremely short. The bond angles for 1 and 2 also exhibit obvious diversity inside of triazacyclononae.

关键词： formation crystal structure protonation triazacyclononane

Parallel personal measurements of diesel engine exhaust and crystalline silica using dual sampling port

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International Journal of Mining Science and Technology 2020年第3期30卷 313-319页

作者： Alan Fleck Caroline Couture Virginie Cabelguen Patrick Eddy Ryan Ross Thuot Guillaume Lachapelle hugo Coulombe Maximilien Debia Department of Environmental and Occupational health University of MontrealMontreal H3T 1A8Canada health and Safety Agnico Eagle MinesToronto M5C 2Y7Canada health and Safety Westwood Mine(IAMGOLD)Preissac J0Y 2E0Canada

Diesel engine exhaust(DEE) and crystalline silica exposures occur simultaneously in the mining industry,and occupational sampling campaigns can be time-and cost-consuming. The authors evaluated a dualport system for simultaneous sampling of DEE and crystalline silica in laboratory and field *** tests evaluated the operation of pumps during 8 h sampling and the intensity of the flow variation for various filter loading conditions and for different modes of operation. Field validation was performed in an underground mine. Pumps operated in constant flow or constant pressure *** in constant flow mode showed that when the flowrate increased on one side of the system, it decreased on the opposite side according to the loading intensity. Tests in constant pressure mode showed that flowrates systematically decreased when using loaded cassettes. however, the higher the backpressure setting, the lower the flow variation was. Flow variations during field tests were generally within the acceptable ±5% range. however, significant flow variations were identified in higher concentrations. A significant negative correlation was found between flowrate variation and total carbon concentration. While the majority of tests support the use of the dual-port for evaluating concomitant exposures, results highlight the possibility of filter overloading as a cause of flowrate changes.

关键词： Crystalline silica Diesel engine exhaust Dual-port Mining Monitoring

OSCILLATIONS OF hIGh ORDER NEUTRAL DIFFERENTIAL EQUATIONS WITh OSCILLATORy COEFFICIENT

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Acta Mathematicae Applicatae Sinica 1991年第2期7卷 135-142页

作者：卢武度 South China Normal Universityonsider the high order neutral differential equation(y(t) +p(t)y(h(t)))~(n)+q(t)y(g(t))=0 (1)where p(t) q(t) h(t) and g(t)∈ C[t_0+∞) q(t)>0 h(t)→∞ g (t)→∞ as t→∞ n≥2.The author studies the oscillation of (1) when p(t) has an arbitrarily large zero and obtainssome sufficient conditions.

Consider the high order neutral differential equation(y(t) +p(t)y(h(t)))^(n)+q(t)y(g(t))=0. (1)where p(t), q(t), h(t) and g(t)∈ C[t_0.+∞);q(t)>0.h(t)→∞, g (t)→∞ as t→∞;n≥*** author studies the oscillation of ... 详细信息

关键词： OSCILLATIONS OF hIGh ORDER NEUTRAL DIFFERENTIAL EQUATIONS WITh OSCILLATORy COEFFICIENT 一夕

On Inventing Cross-Dehydrogenative Coupling(CDC):Forming C-C Bond from Two Different C-h Bonds

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Chinese Journal of Chemistry 2022年第7期40卷 838-845页

作者： Chao-Jun Li Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGill University801 Sherbrooke Street W.MontrealQuebecH3A0B8 Canada

Constructing C-C bonds is central to the synthesis of all chemical *** conventional C-C bond formation methods always require one or two functional groups,20.years ago,our establishment of the concept of Cross-Dehydrogenative Coupling(CDC),wherein C-C bonds are directly formed from two different C-h bonds via the"formal"removal of two h atoms,has revolutionized chemical synthesis and has become one of the most active research subjects in *** perspective article will provide an insight of the origin of this concept and its early development in our laboratory.

关键词： Cross-Dehydrogenative Coupling(CDC) C-h activation Cross-coupling C-C bond formation Green chemistry

The role of oxygen vacancies in metal oxides for rechargeable ion batteries

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Science China Chemistry 2021年第11期64卷 1826-1853页

作者： Runzhe Wei yi Lu yang Xu Department of Chemistry University College LondonLondonWC1H 0AJUK

Rechargeable ion batteries are one of the most reliable energy storage technologies for the applications ranging from small portable devices and electric vehicles to renewable energy integration and large-scale stationary energy *** the roadmap of developing and understanding new electrode materials for rechargeable ion batteries,oxygen vacancies,known as defects in metal oxides,have shown a high impact on the final electrochemical performance of the *** present review aims to summarise the synthesis methods and characterisation techniques of oxygen vacancies as well as some of the most recent and exciting progress made to understand the role of oxygen vacancies in the electrochemical performance of Li-,Na-,K-and Zn-ion *** review discusses not only the role of oxygen vacancies directly in electrode materials and indirectly in the coating layers on electrode materials,but also the synergistic role of oxygen vacancies interplaying with other contributors such as carbonaceous materials,doping,amorphisation,structural transformation,nanostructuring and functional ***,perspectives are given to stimulate new ideas and open questions to facilitate the further development of oxygen deficient electrode materials in energy research landscape.

关键词： oxygen vacancies defect chemistry metal oxide rechargeable ion batteries ion diffusion intercalation reaction conversion reaction

Numerical investigation into pillar failure induced by time-dependent skin degradation

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International Journal of Mining Science and Technology 2017年第4期27卷 591-597页

作者： Sainoki Atsushi Mitri hani S. Department of Mining and Materials Engineering McGill University Montreal H3A0E8 Canada

This paper focuses on the instability mechanism of an isolated pillar, caused by time-dependent skin degradation and strength heterogeneity. The time-dependent skin degradation is simulated with a non-linear rheological model capable of simulating tertiary creep, whereby two different pillar failure cases are investigated. The first case is of an isolated pillar in a deep hard rock underground mine and subjected to high stresses. The results show that pillar degradation is limited to the regions near the surface or the skin until two months after ore extraction. Afterwards degradation starts to extend deeper into the pillar, eventually leaving a highly-stressed pillar core due to stress transfer from the failed *** potential indices show that the risk increases exponentially at the core as time goes by. It is then demonstrated that the progressive skin degradation cannot be simulated with conventional strain-softening model assuming brittle failure. The parametric study with respect to the degree of heterogeneity reveals that heterogeneity is key to the occurrence of progressive skin degradation. The second case investigated in this study is pillar failure taking place in a very long period. Such failure becomes significantly important when assessing the risk for ground subsidence caused by pillar collapse in an abandoned mine. The analysis results demonstrate that the employed non-linear rheological model can simulate gradual skin degradation taking place over several hundred years. The percentage of damage zone volume within the pillar is merely 1% after a lapse of one days and increases to 50. after one hundred years, indicating a high risk for pillar collapse in the long term. The vertical displacements within the pillar also indicate the risk of subsidence. The proposed method is suitable for evaluating the risk of ground surface subsidence above an abandoned mine.

关键词： Pillar stability Underground mine Skin degradation Rheological model Time-dependent failure

Poisson formulas for circular functions on some groups of type h Dedicated to Professor Sheng GONG on the occasion of his 75th birthday

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Science China Mathematics 2006年第11期49卷 1683-1695页

作者： KORNyI Adam Mathematics Dept h h Lehman College BronxN Y 10468USA

Explicit Poisson kernels are found for the subelliptic Dirichlet problem with boundary data satisfying certain symmetry conditions on balls and halfspaces in some heisenberg type groups.

关键词： subelliptic potential theory potential theory on h-type groups with J2 condition subelliptic Dirichlet problem Poisson kernels for h-type groups with J2 condition.

Reevaluating health metrics:Unraveling the limitations of disabilityadjusted life years as an indicator in disease burden assessment

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World Journal of Methodology 2025年第1期15卷 14-19页

作者： Ariel Beresniak Dominique Bremond-Gignac Danielle Dupont Gerard Duru Data Mining International Geneva 1216Switzerland Department of Ophtalmology Necker-Enfants Malades University HospitalAP-HPParis-CitéUniversityINSERMUMRS1138Team 17From Physiopathology of Ocular Diseases to Clinical DevelopmentSorbonne Paris CitéUniversityCentre de Recherche des CordeliersParis 75015France Data Mining America Montreal H2YCanada

In 1993,the World Bank released a global report on the efficacy of health promotion,introducing the disability-adjusted life years(DALy)as a novel *** DALy,a composite metric incorporating temporal and qualitative data,is grounded in preferences regarding disability *** review delineates the algorithm used to calculate the value of the proposed DALy synthetic indicator and elucidates key methodological challenges associated with its *** contrast to the quality-adjusted life years approach,derived from multi-attribute utility theory,the DALy stands as an independent synthetic indicator that adopts the assumptions of the Time Trade Off utility technique to define Disability *** to rely on no mathematical or economic theory,DALy users appear to have exempted themselves from verifying whether this indicator meets the classical properties required of all indicators,notably content validity,reliability,specificity,and *** DALy concept emerged primarily to facilitate comparisons of the health impacts of various diseases globally within the framework of the Global Burden of Disease initiative,leading to numerous publications in international *** widespread adoption,the DALy synthetic indicator has prompted significant methodological concerns since its inception,manifesting in inconsistent and non-reproducible *** the substantial diffusion of the DALy indicator and its critical role in health impact assessments,a reassessment is *** reconsideration is imperative for enhancing the robustness and reliability of public health decisionmaking processes.

关键词： Disability adjusted life years Cost-utility analyses Outcome research Public health Burden of disease