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Nuclear Science and Techniques 2020年第4期31卷 16-28页

作者： Shi-chang Zhang Shun-Yan Ning Jie zhou Si-Yi Wang Wei Zhang xin-Peng Wang Yue-zhou Wei Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials School of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004China School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

A porous silica-polymer-based adsorbent,isoBuBTP/Si O2-P,was prepared by a vacuum impregnation method and used for the recovery of ruthenium,rhodium,and palladium from nitric acid *** experimental results revealed that iso Bu-BTP/SiO2-P exhibited unique adsorption properties such as high saturation adsorption capacity(Ru:0.35 mmol g^-1,Rh:0.32 mmol g^-1,Pd:1.05 mmol g^-1)and excellent selectivity over other metal ions,such as lanthanides(SF(PGM/M)>40)in 1 M HNO3 *** adsorption process conformed to the pseudosecond-order model and Langmuir *** the UV,FTIR,and XPS analyses,it can be concluded that the strong affinity between functional groups(C–N=C)and metal ions as well as NO3-played a role in coordination during the adsorption ***,the desorption behavior was studied,and it was found that the adsorbed Pd,Rh,and Ru could be eluted with a 0.01 M nitric acid–0.1M thiocarbamide solution,5M hydrochloric acid,and sodium hypochlorite(CP)solution,***,based on those findings,a simple process for the separation and recovery of Pd,Rh,and Ru from high-level liquid waste using iso Bu-BTP/SiO2-P was designed and proposed.

关键词： BTP Adsorption Ruthenium Rhodium Palladium High-level liquid waste

Development and application of an efficient virus-induced gene silencing system in Nicotiana tabacum using geminivirus alphasatellite

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第2期12卷 83-92页

作者： chang-jun HUANG Tong ZHANG Fang-fang LI xin-yue ZHANG Xue-ping zhou State Key Laboratory of Rice Biology Institute of Biotechnology Zhejiang University Hangzhou 310029 China

Virus-induced gene silencing (VIGS) is a recently developed technique for characterizing the function of plant genes by gene transcript suppression and is increasingly used to generate transient loss-of-function assays. Here we report that the 2mDNA1, a geminivirus satellite vector, can induce efficient gene silencing in Nicotiana tabacum with Tobacco curly shoot virus. We have successfully silenced the β-glucuronidase (GUS) gene in GUS transgenic N. tabacum plants and the sulphur desaturase (Su) gene in five different N. tabacum cultivars. These pronounced and severe silencing phenotypes are persistent and ubiquitous. Once initiated in seedlings, the silencing phenotype lasted for the entire life span of the plants and silencing could be induced in a variety of tissues and organs including leaf, shoot, stem, root, and flower, and achieved at any growth stage. This system works well between 18-32°C. We also silenced the NtEDS1 gene and demonstrated that NtEDS1 is essential for N gene mediated resistance against Tobacco mosaic virus in N. tabacum. The above results indicate that this system has great potential as a versatile VIGS system for routine functional analysis of genes in N. tabacum.

关键词： Virus induced gene silencing Geminivirus Alphasatellite Nicotiana tabacum

Activity of Azoxystrobin and SHAM to Four Phytopathogens

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Agricultural Sciences in China 2009年第7期8卷 835-842页

作者： JIN Li-hua CHEN Yu CHEN chang-jun WANG Jian-xin zhou Ming-guo College of Plant Pathology Nanjing Agricultural University Nanjing 210095 P.R.China

The study was conducted to make clear the activity of azoxystrobin to 4 plant pathogens and the synergistic effects of salicylhydroxamic acid （SHAM）, which acted on the alternative oxidase. It was also conducted to be aware of the mechanism of azoxystrobin in inhibition on mycelial respiration and the influence of SHAM. The activity test of azoxystrobin and SHAM was carried out with a mycelial linear growth test and spore germination test. Other related biological properties were also observed. Inhibition of azoxystrobin and SHAM on 4 pathogens was determined by using SP-II oxygraph system. Azoxystrobin inhibited mycelial growth in Colletotrichum capsici, Botrytis cinerea, Rhizoctonia solani, and Magnaporthe grisea, respectively; it also inhibited conidia germination, and conidia production in C. capsici, B. cinerea M. grisea, and sclerotia formation in R. solani. Moreover, it created stayed pigment biosynthesis in C. capsici and M. grisea somehow. Salicylhydroxamic acid enhanced inhibition by azoxystrobin. An oxygen consuming test of the mycelia showed that azoxystrobin inhibited all the 4 fungi＇s respiration in the early stages. With the concentration rising up, the effectiveness increased. However, as time went on, the respiration of the mycelia treated with fungicides recovered and SHAM could not inhibit the oxygen consuming. This reaction between the mycelia and the fungicides appeared not to initiate alternative respiration but rather the other mechanism created a lack of efficacy.

关键词： azoxstrobin salicylhydroxamic acid (SHAM) plant pathogens spore germination mycelial growth oxygenconsumption rate

Optimal design of feeding system in steel casting by constrained optimization algorithms based on InteCAST

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China Foundry 2016年第6期13卷 375-382页

作者： chang-chun Dong Xu Shen Jian-xin zhou Tong Wang Ya-jun Yin State Key Laboratory of Materials Processing and Die & Mould Technology Huazhong University of Science and Technology

The traditional foundry industry has developed rapidly in recently years due to advancements in computer technology. Modifying and designing the feeding system has become more convenient with the help of the casting software, Inte CAST. A common method of designing a feeding system is to first design the initial systems, run simulations with casting software, analyze the feedback, and then redesign. In this work, genetic, fruit fly, and interior point optimizer(IPOPT) algorithms were introduced to guide the optimal riser design for the feeding system. The results calculated by the three optimal algorithms indicate that the riser volume has a weak relationship with the modulus constraint; while it has a close relationship with the volume constraint. Based on the convergence rate, the fruit fly algorithm was obviously faster than the genetic algorithm. The optimized riser was also applied during casting, and was simulated using Inte CAST. The numerical simulation results reveal that with the same riser volume, the riser optimized by the genetic and fruit fly algorithms has a similar improvement on casting shrinkage. The IPOPT algorithm has the advantage of causing the smallest shrinkage porosities, compared to those of the genetic and fruit fly algorithms, which were almost the same.

关键词： casting process design optimal solution Inte CAST

A gauge theory for two-band model of Chern insulators and induced topological defects

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Communications in Theoretical Physics 2022年第1期74卷 124-133页

作者： Zhi-Wen chang Wei-chang Hao xin Liu Institute of Theoretical Physics Faculty of SciencesBeijing University of TechnologyBeijing 100124China School of Physics Beihang UniversityBeijing 100191China

In this paper a gauge theory is proposed for the two-band model of Chern *** on the so-calle't Hooft monopole model,a U(1)Maxwell electromagnetic sub-field is constructed from an SU(2)gauge field,from which arise two types of topological defects,monopoles and e2 *** focus on the topological number in the Hall conductance σ_(xy)=e^(2)/hC,where C is the Chern *** is discovered that in the monopole case C is indeterminate,while in the meron case C takes different values,due to a varying on-site energy *** a typical example,we apply this method to the square lattice and compute the winding numbers(topological charges)of the defects;the C-evaluations we obtain reproduce the results of the usual ***,based on the gauge theory we propose a new model to obtain the high Chern numbers|C|=2,4.

关键词： Chern insulator Chern number monopole meron

Effects of seven different companion plants on cucumber productivity, soil chemical characteristics and Pseudomonas community

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Journal of Integrative Agriculture 2017年第10期16卷 2206-2214页

作者： chang Chun-ling FU Xue-peng zhou xin-gang GUO Mei-yu WU Feng-zhi Department of Horticulture Northeast Agricultural University Harbin 150030 P.R.China

Companion cropping can influence cucumber productivity by altering soil chemical characteristics and microbial communities. However, how these alterations affect the growth of cucumber is still unknown. In this study, seven different plant species were selected as companion plants for testing their effects on cucumber productivity. The effects of different companion plants on changes in soil chemical properties such as electrical conductivity （EC） and contents of essential nutrients as well as the structure and abundance of the soil Pseudomonas community were evaluated. The results showed a higher cucumber yield in the wheat/cucumber companion system than that in the cucumber monocultured and other companion cropping systems. The lowest phosphorus （P） and potassium （K） contents in the soil were found in the cucumber monocultured system, and the highest NO3＋-N and NH4＊-N contents were observed in the rye/cucumber companion system. PCR-denaturing gradient gel electrophoresis （DGGE） and real-time PCR analysis showed that the trifolium/cucumber companion system increased the diversity of the soil Pseudomonas community, while the chrysanthemum/cucumber companion system increased its abundance. Interestingly, plant-soil feedback trials revealed that inoculating the soil of the wheat/cucumber companion system increased the growth of cucumber seedlings. In conclusion, the effects of different companion plants on cucumber productivity, soil chemical characteristics and the soil Pseudomonas community were different, and wheat was a more suitable companion plant for increasing cucumber productivity. In addition, the altered microbial community caused by companion cropping with wheat contributed to increased cucumber productivity.

关键词： cucumber companion plants soil chemical characteristics Pseudomonas community

Influence of phosphorous on nucleation and growth of grains during solidification in a NiCrFe alloy

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Journal of Materials Science & Technology 2019年第1期35卷 134-141页

作者： xintong Lian Wenru Sun Litao chang Fang Liu xin xin Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

The influence of phosphorus on the solidification of a NiCrFe model alloy has been investigated through a series of analytical techniques. It was found that increasing phosphorous additions greatly influenced the as-cast microstructure, changing from equiaxed grains to columnar grains in the center of ingots. It is indicated that the increase of phosphorous reduced the nucleation of grains and promoted dendrite growth during solidification. Furthermore, the addition of phosphorus in alloys also caused the segregation and phase transformation at grain boundaries and in interdendritic regions. The mechanism by which phosphorus influence the solidification of alloys was discussed based on experimental results as well.

关键词： NiCrFe alloy Phosphorus Segregation Nucleation Grain growth

Highly efficient enantioselective synthesis of bispiro[benzofuran-oxindole/benzofuran-chromanone]s through organocatalytic inter-/intramolecular Michael cycloaddition

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Chinese Chemical Letters 2020年第2期31卷 381-385页

作者： Min Zhang Jun-xin Wang Shun-Qin chang Xiong-Li Liu Xiong Zuo Ying zhou Guizhou Engineering Center for Innovative Traditional Chinese Medicine and Ethnic Medicine Guizhou UniversityGuiyang 550025China College of Pharmaceutical Sciences Guizhou University of Traditional Chinese MedicineGuiyang 550025China

A quinine-derived thiourea-catalyzed inter-/intramolecular Michael cycloaddition of chromoneoxindole/benzofuranone synthons with 3-substituted methylenebenzofuranones has been established,which constructed enantiomerically pure bispiro[benzofuran-oxindole/benzofuran-chromanone]s bearing five consecutive stereocenters including two spiro quaternary carton centers in good yields(up to 93%) with high diastereoselectivities(up to>20:1 dr) and good enantioselectivities(up to>99% ee).Moreover,this is the first example of bifunctional chromone-benzofuranone synthon directed organocatalytic tandem reaction,and also the first example of the bispiro[benzofuran-oxindole] and bispirobenzofuranone,potentially useful in medicinal chemistry.

关键词： Chromone-oxindole synthon Chromone-benzofuranone synthon Inter-/intramolecular Michael cycloaddition Bispiro[benzofuran-oxindole-chromanone] Bispirobenzofuranone

Investigation on the Hydro-forming of SUS304 Stainless Steel Dome

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Chinese Journal of Aeronautics 2006年第B12期19卷 261-264页

作者： XU Yong-chao YUAN Shi-jian CHEN Yu zhou Li-xin KANG Da-chang School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The dome hydro-forming was studied theoretically and experimentally. The theoretical analysis shows that the process of dome hydro-forming can be divided into two stages, i.e., firstly forming a hemi-sphere and secondly forming a hemi-toroidal. Theoretically, being larger than those in the outer area of a hemi-toroidal shell, the radial tensile stresses take place in the inner area where fracture is more likely to occur in the forming process. The required hydraulic pressure to form the dome should be determined by the deformation in the outer area, hitting about 12 MPa in theory. The experimental results show that the dome could be produced in one operation by hydro-forming which needs a hydraulic pressure of about 9 MPa. The experimental results prove to agree well with the theoretical analysis. In order to avoid wrinkling and fracture, the closing force acted on the die should be adjusted properly in accordance with the hvdraulic nressure.

关键词： hydro-forming dome SUS304 stainless steel

Rapid Identification of Bibenzyls of Stemona sessilifolia using Hyphenated LC-UV-NMR and LC-MS Methods

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Chemical Research in Chinese Universities 2007年第1期23卷 48-51页

作者： YANG xin-zhou YANG Yi-ping TANG Chun-ping KE chang-qiang YE Yang State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 P. R. China

As a part of the ongoing search for new constituents of Stemona species in China, chemical investigation of Stemona sessilifolia, a plant used in the traditional Chinese medicine to treat respiratory disorders, was carried out. To identify the chemical components rapidly, a selected sample of S. sessilifolia containing bibenzyls was tested using LC-ESIMS and analyzed further using stop-flow LC-UV-NMR, which was sensitive for the detection of the main constituents. LC microfractions were collected using the LC-UV-NMR technique and HR-EIMS off-line analysis was cartied out on the collected fractions. This chemical screening strategy allowed for the on-line identification of the main constituents of S. sessilifolia and provided information that was useful for a further peak-guided isolation procedure. Using these methods, four bibenzyls were isolated： two known compounds, 3,5-dihydroxy-4-methyl bibenzyl（1） and 3, 5-dihydroxy-2＇-methoxy-4-methyl bibenzyl （ 2 ）, and two novel compounds, 3,3＇-dihydroxy-5, 6＇-dimethoxy bibenzyl（3） and 3,5-dihydroxy-2＇, 5＇-dimethoxy bibenzyl （4）.

关键词： Bibenzyls LC-UV-NMR Stemona sessilifolia