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An Equation of Stirling Numbers of the Second Kind

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Chinese Quarterly Journal of Mathematics 2006年第2期21卷 261-263页

作者： DU Chun-yu zhang Jian-guo College of Mathematice and Information Science Henan University Kaifeng 475001 China

In this paper, We propose and prove the following equation, where {3^n} is a stirling number of the second kind, when n ≥ 3 is given.

关键词： combinations stirling numbers of the second kind

Soil shear properties as infl uenced by straw content:An evaluation of field-collected and laboratory-remolded soils

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Journal of Integrative Agriculture 2016年第12期15卷 2848-2854页

作者： FANG Hui-min zhang Qing-yi JI Chang-ying guo Jun College of Engineering Nanjing Agricultural University

Following a rice or wheat harvest, a large amount of crop residue （straw） is retained in fields. The straw is often incorporated into the soil in order to increase the soil organic carbon storage and to reduce soil erosion. However, it has become apparent that the incorporated straw can significantly alter soil shear properties, which can dramatically affect energy inputs for tilling and other soil management practices. In this study, laboratory-remolded wheat straw-soil samples were compared with field-collected straw-soil samples; we found high correlations for the cohesion （R2=0.9084） and internal friction angle （R2=0.9548） properties of the samples. Shear tests on rice and wheat straw with different moisture content levels clearly demonstrated the relatively higher shear strength of wheat straw compared to rice straw. The cohesion of remolded rice and wheat straw-soil samples exhibited an increasing linear trend with an increase in densities, whereas the internal friction angle data for these samples exhibited a quadratic trend. Overlapping the cohesion curves revealed that the wheat straw-soil and rice straw-soil samples had the same cohesion at a straw density of 0.63%. Similar results were obtained when the internal fraction angle curves overlapped; the resultant point of intersection was observed at a straw density of 0.46%. As a whole, the remolded sample methodology was found suitable to simulate the shear properties of soils sampled directly from fields.

关键词： direct shear test wheat straw rice straw cohesion internal friction angle

重庆温光敏核不育小麦C49S的育性稳定性分析

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麦类作物学报 2007年第5期27卷 787-790页

作者：张亚勤宗学凤余国东张建奎西南大学农学与生物科技学院重庆400716 重庆市农科院特色作物研究所重庆402160

为了研究重庆温光敏核不育小麦C49S在杂种优势利用中的价值,根据7年田间分期播种试验结果分析了C49S年度间的育性稳定性及其可育与不育的临界播种期。结果表明,在气温正常年份,C49S随着播期的变化表现出“完全不育—半不育—高度可育”... 详细信息

为了研究重庆温光敏核不育小麦C49S在杂种优势利用中的价值,根据7年田间分期播种试验结果分析了C49S年度间的育性稳定性及其可育与不育的临界播种期。结果表明,在气温正常年份,C49S随着播期的变化表现出“完全不育—半不育—高度可育”的育性转换特性,且在不同年份间育性转换特性稳定;在重庆,10月31日是C49S的不育临界播种期,在此之前播种表现完全不育或高度不育,自交结实率在5%以下;12月10日是其正常可育的临界播种期,在此之后播种表现正常可育,自交结实率在50%以上;11月10日至11月30日之间播种,处于半不育状态,自交结实率为5%-50%。可以通过调整其播期来进行制种或繁殖。

关键词：小麦温光敏核不育育性稳定性临界播种期

Constitutive analysis and optimization on hot working parameters of as-cast high Cr ultra-super-critical rotor steel with columnar grains

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Journal of Iron and Steel Research International 2017年第9期24卷 916-924页

作者： Zong-ye Ding Di zhang Qiao-dan Hu Long Zeng Jian-guo Li School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of Materials Laser Processing and Modification Shanghai Jiao Tong UniversityShanghai 200240China

Isothermal hot compression tests on the as-cast high-Cr ultra-super-critical rotor steel with columnar grains were carried out in the temperature range from 1223 to 1523Kand at strain rates from 0.001 to 1s^（-1）.The compression direction was parallel to the longitudinal direction of columnar *** constitutive equation based on Arrhenius model was presented,and the processing maps based on the dynamic material model were developed,correlating with microstructure *** main softening mechanism was dynamic recovery at 1223 Kunder strain rates from 0.1to 1s^（-1）,whereas it was dynamic recrystallization under other deformation *** constitutive equation modified by strain compensation reasonably predicted the flow *** processing maps and microstructure evolution mechanism schematic indicated that the optimum hot working parameters lay in the zone defined by the temperature range from 1423 to 1473Kand the strain rate range from 0.001 to 1s^（-1）.

关键词： As-cast ultra-super-critical rotor steel Columnar grain Dynamic recrystallization Modified constitutive equation Processing map

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套筒长度对火焰筒流场和雾化特性的影响

航空动力学报 2009年第11期24卷 2506-2513页

作者：于锦峰郭志辉张君锋尚守堂北京航空航天大学能源与动力工程学院航空发动机气动热力科技重点实验室北京100191 中国航空工业集团公司沈阳航空发动机设计研究所沈阳110015

利用激光粒子动态分析仪实验研究了套筒长度对火焰筒头部的流场和喷雾场的影响.结果表明:套筒长度控制流场的发展,影响顺流区壁面再附点的位置,随着套筒长度的增加,再附点向下游移动.套筒的长度存在一个临界值,使中心回流区的尺寸最大.... 详细信息

利用激光粒子动态分析仪实验研究了套筒长度对火焰筒头部的流场和喷雾场的影响.结果表明:套筒长度控制流场的发展,影响顺流区壁面再附点的位置,随着套筒长度的增加,再附点向下游移动.套筒的长度存在一个临界值,使中心回流区的尺寸最大.套筒对雾化的影响较大,在回流区内,套筒长度最小时雾化效果较好.在顺流区内,液雾的索太尔平均直径随着套筒长度的增加而逐渐减小.套筒加长时喷雾锥角有所减小.套筒的最佳长度选择需要综合考虑燃烧室的具体设计要求.

关键词：旋流杯套筒流场雾化

Effect of high-voltage thermal breakdown on pore characteristics of coal

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International Journal of Mining Science and Technology 2017年第6期27卷 1051-1055页

作者： Zhu Chuanjie Lu Ximiao Gao Zishan Yan Fazhi guo Chang zhang Xiangliang State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University School of Safety Engineering China University of Mining and Technology

High-voltage thermal breakdown has great potential application in permeability enhancement of coal seam. The characteristics of the breakdown channel, coal element, porosity and microscopic coal petrography of coal under high-voltage electric load were experimentally studied. The coal interior left apparent tracks due to electric current burning with high temperature. The percentage of C, O, Al, Fe, and Si had slightly decreased, while the content of element N increased obviously. Low-pressure nitrogen gas adsorption(LP-N_2GA) and mercury intrusion analysis showed that coal porosity increased. The increases of micropores and mesopores are beneficial to promotion of the ability of gas storage, and the increase of macropores could enhance the gas seepage and migration. The results of scanning electron microscope(SEM) show that there are many exogenous fractures in coal, which is also beneficial to gas seepage and migration. The results lay a theoretical foundation for application of high-voltage thermal breakdown in coal mines.

关键词： High-voltage thermal breakdown Permeability enhancement Porosity Fracture Gas adsorption

Visible light induced cross-coupling synthesis of asymmetrical heterobiaryls using Pd/CeO_2 nanocomposite photocatalyst

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Chinese Chemical Letters 2018年第6期29卷 903-906页

作者： Yanqin Ge Pinhui Diao Chen Xu Nannan zhang Cheng guo College of Chemistry and Molecular Engineering Nanjing Tech University

A simple, mild and green approach has been developed for the synthesis of asymmetrical heterobiaryls under the irradiation of visible light without any oxidants and promoting reagents through using Pd/Ce O2 nanocomposite photocatalyst. This method can tolerate considerable functional groups such as electrondonating groups and electron-withdrawing groups through CààC cross-coupling. Moreover, we obtain the products with moderate yields in an efficient way. Finally, a plausible mechanism is proposed.

关键词： Visible light Nanocomposite photocatalyst Pd/CeO2 C—C cross-coupling Mild condition

Drought tolerance in three hybrid poplar clones submitted to different watering regimes

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Journal of Plant Ecology 2010年第2期3卷 79-87页

作者： Xiao-yun guo Xin-Shi zhang Zhen-Ying Huang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Graduate University of Chinese Academy of Sciences Beijing 100049China

Aims Poplars grownin North Chinamay experience water-deficient periods in their life *** aim of the present paper was to quantify the response of three clones to different watering regimes and to determine whichcloneamongthe three is the best adapted to drought *** Three hybrid poplar clones(clone DN-34,R-247 and OP-367)were used in the present *** seedlings of the three clones were grown under four watering regimes:control(well watered,100%field water capacity(FC))and three drought treatments(drought stress I,50%FC;drought stress II,40%FC;drought stress III,30%FC).Changes in morphological,physical and biochemical indicators of the three hybrid poplar clones were *** Findings Drought treatment(50%,40%and 30%FC)decreased net photosynthetic rate(Pn),transpiration rate(Tr),stomatal conductance(gs),shoot height,total biomass and chlorophyll(Chl)content in all the three clones and it increased activities of antioxidant enzymes and free proline *** highest values of the above-mentioned morphological and physiological parameters were recorded in clone OP-367 under 30%FC,followed by clone DN-34 and *** leaf water content(RWC)and stem diameter(sd)markedly declined in clone R-247 and DN-34 under drought stress I,II and III,whereas RWC and sd declined in clone OP-367 only under drought stress II and *** OP-367 had more RWC and sd than DN-34 and *** the 30%FC induced an increase in the root-to-shoot ratio(rs)and water use efficiency(WUE)in all the three ***-367 was the most efficient clone in water absorption and use,for plants of the clone had the highest values of rs and *** data demonstrate that among the three clones,OP-367 was better able to maintain photosynthesis and growth and lower the damage caused by drought.

关键词： antioxidant enzyme drought tolerance growth hybrid poplar clone leaf gas exchange

Treatment of abdominal compartment syndrome in severe acute pancreatitis patients with traditional Chinese medicine

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World Journal of Gastroenterology 2008年第22期14卷 3574-3578页

作者： Min-Jie zhang guo-Lei zhang Wen-Bin yuan Jun Ni Li-feng Huang Department of General surgery Affiliated Central Hospital of Huzhou Normal College Huzhou 313000 Zhejiang Province China Research Center of Biomedicine and Health Hangzhou Normal University Hangzhou 310000 Zhejiang Province China

AIM: To investigate the therapeutic effect of traditional Chinese traditional medicines Da Cheng Qi Decoction (Timely-Purging and Yin-Preserving Decoction) and Glauber's salt combined with conservative measures on abdominal compartment syndrome (ACS) in severe acute pancreatitis (SAP) patients. METHODS: Eighty consecutive SAP patients, admitted for routine non-operative conservative treatment, were randomly divided into study group and control group (40 patients in each group). Patients in the study group received Da Cheng Qi Decoction enema for 2 h and external use of Glauber's salt, once a day for 7 d. Patients in the control group received normal saline (NS) enema. Routine non-operative conservative treatments included non-per os nutrition (NPON), gastrointestinal decompression, life support, total parenteral nutrition (TPN), continuous peripancreatic vascular pharmaceutical infusion and drug therapy. Intra-cystic pressure (ICP) of the two groups was measured during treatment. The effectiveness and outcomes of treatment were observed and APACHE Ⅱ scores were applied in analysis. RESULTS: On days 4 and 5 of treatment, the ICP was lower in the study group than in the control group(P < 0.05). On days 3-5 of treatment, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) scores for the study and control groups were significantly different (P < 0.05). Both the effectiveness and outcome of the treatment with Da Cheng Qi Decoction on abdominalgia, burbulence relief time, ascites quantity, cyst formation rate and hospitalization time were quite different between the two groups (P < 0.05). The mortality rate for the two groups had no significant difference. CONCLUSION: Da Cheng Qi Decoction enema and external use of Glauber's salt combined with routine non-operative conservative treatment can decrease the intra-abdominal pressure (IAP) of SAP patients and have preventive and therapeutic effects on abdominal compartment syndrome of SAP.

关键词： Da Cheng Qi Decoction Glauber's salt traditional Chinese medicine Severe acute pancreatitis Abdominal compartment syndrome