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Note on a Conjecture of Gopakumar-Vafa

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Chinese Annals of Mathematics,Series B 2006年第2期27卷 219-242页

作者： jun li Baosen wu Dedicated to the memory of Shiing-Shen Chern

We rephrase the Gopakumar-Vafa conjecture on genus zero Gromov-Witten invariants of Calabi-Yau threefolds in terms of the virtual degree of the moduli of pure dimension one stable sheaves and investigate the conjectur... 详细信息

关键词： Calabi-Yau threefold Gromov-Witten invariants Moduli of stable sheaves

Thermal test and numerical simulation of cooling stave with internal ribbed tube

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Journal of Iron and Steel Research International 2022年第8期29卷 1194-1204页

作者： Xun Xu li-jun wu Zhao-kuo Yuan Xinglin College Nantong UniversityNantong 226000JiangsuChina School of Mechanical Engineering Tongji UniversityShanghai 201804China

A new type of cooling stave with internal ribbed tube was proposed,and the heat transfer performance of the stave was studied by means of thermal test and numerical *** temperature of cooling stave was monitored in the conditions of furnace gas temperature of 200-700 C and cooling water velocity of 0.2-1.0 m/*** thermal test results show that the internal rib structure can form swirl in the water pipe and improve the cooling capacity of the cooling *** higher the furnace temperature or the lower the cooling water flow rate,the more obvious the advantage of the cooling stave with internal ribbed *** mathematical model of the cooling stave with internal ribbed tube was established by FLUENT software,and the influence of the internal rib structure parameters on the heat transfer performance of the cooling stave was *** is suggested that the parameters of the internal ribbed tube should be 4 ribs,1 mm in height,5-7 mm in width,and 20-30 mm in *** the same common working conditions of the cooling stave,the maximum temperature of the newly designed cooling stave with internal ribbed tube is reduced by 5.6%compared with that of common cooling stave with round *** water flow rate in the internal ribbed tube only needs 0.9 m/s to reach the cooling effect of 2 m/s in the common tube cooling stave,which can save 55%of *** case of water shortage accident of cooling stave,the maximum temperature of the cooling stave with internal ribbed tube is decreased by 22.4%compared with that of common round tube,which can effectively reduce the harm of water shortage and protect the cooling stave.

关键词： Cooling stave Internal ribbed tube Heat transfer Thermal test Numerical simulation

A relative feasibility degree based approach for constrained optimization problems

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第4期11卷 249-260页

作者： Cheng-gang CUI Yan-jun li Tie-jun wu Department of Control Science and Engineering Zhejiang University Hangzhou 310027 China

Based on the ratio of the size of the feasible region of constraints to the size of the feasible region of a constrained optimization problem,we propose a new constraint handling approach to improve the efficiency of heuristic search methods in solving the constrained optimization *** the traditional classification of a solution candidate,it is either a feasible or an infeasible *** refine this classification,a new concept about the relative feasibility degree of a solution candidate is proposed to represent the amount by which the 'feasibility' of the solution candidate exceeds that of another *** feasibility degree based selection rules are also proposed to enable evolutionary computation techniques to accelerate the search process of reaching a feasible *** addition,a relative feasibility degree based differential evolution algorithm is derived to solve constraint optimization *** proposed approach is tested with nine benchmark *** indicate that our approach is very competitive compared with four existing state-of-the-art techniques,though still sensitive to the intervals of control parameters of the differential evolution.

关键词： Constrained optimization Evolutionary computation Relative feasibility degree(RFD) Evolution differential algorithm

Two new acetylated ginsenosides from the roots of Panax quinquefolium

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Chinese Chemical Letters 2008年第9期19卷 1099-1102页

作者： Ji Ming Jia li jun wu School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China Hebei Province Traditional Chinese Medicine and Western Medicine Institute of Pharmaceutical Shijiazhuang 050035 China

Two new acetylated ginsenosides, 20（S）-protopanaxatriol-6-O-α-L-rhamnopyranosyl （1 → 2）-β-D-6＇-O-acetylglucopyranoside （1） and 20（R）-protopanaxatrol-6-O-α-L-rhamnopyranosyl （1 → 2）-β-o-6＇-O-acetylglucopyranoside （2）, were isolated from the roots of Panax quinquefolium. The structures were elucidated on the basis of spectroscopic techniques and chemical means.

关键词： Panax quinquefolium Araliaceae Acetylated ginsenoside

Characterization of heat shock protein 90, 70 and their transcriptional expression patterns on high temperature in adult of Graphofita molesta （Busck）

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Insect Science 2014年第4期21卷 439-448页

作者： Hao Chen Xiang-li Xu Yi-Ping li jun-Xiang wu Key Laboratory of Plant Protection Resources and Pest Management (Northwest A&F University) Ministry of Education Key Laboratoryof Appfied Entomology Northwest A&F University Yangling Shaanxi China

Grapholita molesta （Busck） is a worldwide insect pest damaging stone and pome fruits. High temperature can significantly affect insect survival, development and fecundity. Heat shock protein （Hsp） genes were speculated to possess a pivotal function in response to high temperature stress. In this study, two full-length Hsp genes, Gmhsp90 and GmhspTO, were cloned from G. molesta using rapid amplification of complementary DNA ends （RACE）. The open reading frames of Gmhsp90 and Gmhsp70 obtained were 2 148 bp and 1 998 bp in length, respectively. Their deduced amino acids showed high homology to Hsp genes of other species. Subsequently, the transcriptional expression of Gmhsp90 and Gmhsp70 in G. molesta adults exposed at various temperatures （26, 29, 32, 35, 38, 41 and 44℃） for 1 h and at 41℃ for various time duration （0, 15, 30, 45, 60, 75, 90 and 105 min） were investigated via real time quantitative polymerase chain reaction （qPCR）. The relative expression levels of Gmhsp90 and Gmhsp70 in G. molesta adults were both up-regulated with the rise of temperature and time duration. In addition, the Gmhsp70 usually showed a higher transcription accumulation than Gmhsp90. Interestingly, Gmhsp90 and Gmhsp 70 in female adults could be induced much earlier than that in males, and the effective induction temperature in females was also lower than that in males. The distinct expression profiles of Gmhsp90 and Gmhsp 70 indicated that Gmhsp90 and Gmhsp 70 may play important roles in G. molesta adults responding to a thermal threat, and there is difference on induction between sexes.

关键词： Grapholita molesta heat shock protein high temperature sex difference

A New Sesquiterpene from Transformation of Curdione by Cell Suspension Culture of Platycodon Grandiflorum

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Chinese Chemical Letters 2005年第11期16卷 1487-1488页

作者： Xiao Chi MA li jun wu De An GUO The State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Beijing 100083 School of Traditional Chinese Medicines Shenyang Pharmaceutical University Shengyang 110016

A new sesquiterpene was isolated from transformation of curdione by cell suspension culture of Platycodon grandiflorum. The structure of the new compound was elucidated on the basis of spectral methods including 2D NMR.

关键词： Platycodon grandiflorum biotransformation curdione sesquiterpene.

A new compound with cytotoxic activities from the leaves of Panax ginseng C.A. Meyer

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Chinese Chemical Letters 2008年第7期19卷 837-840页

作者： li Bo Wang Zhao Hua wu Hui Yuan Gao Jian Huang Bo Hang Sun li jun wu School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China Department of Pharmacology Mudanjiang Medical College Mudanjiang 157001 China

A new compound, 3,6,20（S）-trihydroxy- 12,23-epoxydammar-24-ene,6,20-di-O-β-D-glucopyranoside （1）, was isolated from the leaves of Panax ginseng C.A. Meyer, whose structural elucidation was carried out by means of spectral analysis （including IR, HR- FAB-MS and NMR）. This compound showed the moderate cytotoxic activities against U937 and HeLa cells by using the MTT method.

关键词： Panax ginseng 3,6,20(S)-Trihydroxy-12,23-epoxy-dammar-24-ene,6,20-Di-O-β-D-glucopyranoside Cytotoxic activity

A new isoquinoline derivative from the leaves of Magnolia sieboldii ***

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Chinese Chemical Letters 2010年第12期21卷 1446-1448页

作者： Di wu Ru Ping Wang Shao Jiang Song li jun wu Hui Yuan Gao The liaoning Provincial Public Security Office Shenyang 110032 China School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education Shenyang Pharmaceutical University Shenyang 110016 China

Magnoline（1）,a new isoquinoline derivative,was isolated from the leaves of Magnolia sieboldii ***（Magnoliaceae）.Its structure was elucidated on the basis of spectral analysis including 1D,2D NMR and HR-TOF-MS.

关键词： Magnolia sieboldii K. Koch Isoquinoline Structural identification

Metal-doped(Cu,Zn)Fe2O4 from integral utilization of toxic Zn-containing electric arc furnace dust: An environment-friendly heterogeneous Fenton-like catalyst

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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 996-1006页

作者： jun-wu li Xing Han Rong-xia Chai Fang-qin Cheng Mei Zhang Min Guo State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China Shanxi Collaborative Innovation Center of High Value-added Utilization of Coal-related Wastes Shanxi UniversityShanxi 030006China

Pure metal-doped(Cu,Zn)Fe2O4 was synthesized from Zn-containing electric arc furnace dust(EAFD)by solid-state reaction using copper salt as *** effects of pretreated EAFD-to-Cu2(OH)2CO3·6H2O mass ratio,calcination time,and calcination temperature on the structure and catalytic ability were systematically *** the optimum conditions,the decolorization efficiency and total organic carbon(TOC)removal efficiency of the as-prepared ferrite for treating a Rhodamine B solution were approximately 90.0%and 45.0%,respectively,and the decolorization efficiency remained 83.0%after five recycles,suggesting that the as-prepared(Cu,Zn)Fe2O4 was an efficient heterogeneous Fenton-like catalyst with high *** high catalytic activity mainly depended on the synergistic effect of iron and copper ions occupying octahedral *** importantly,the toxicity characteristic leaching procedure(TCLP)analysis illustrated that the toxic Zncontaining EAFD was transformed into harmless(Cu,Zn)Fe2O4 and that the concentrations of toxic ions in the degraded solution were all lower than the national emission standard(GB/31574-2015),further confirming that the as obtained sample is an environment-friendly heterogeneous Fenton-like catalyst.

关键词： Zn-containing electric arc furnace dust metal-doped Cu−Zn ferrite heterogeneous Fenton-like catalyst environmental effect