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Issues in the outburst prevention work of coal mines in Guizhou Province and the analysis of its countermeasures

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Journal of Coal Science & Engineering(China) 2011年第2期17卷 152-156页

作者： li qing-song li Xiao-hua MA Shu Guizhou Mine Safety Scientific Research Institute Guiyang 550025 China Guizhou Coal Mine Design and Research Institute Guiyang 550025 China

In order to reduce the occurrence of coal and gas outburst accidents, and improve the capability to prevent gas hazards and realize the safe and efficient mining of coal enterprises. The distribution of the outburst coal mining area of Guizhou Province and the status of coal and gas outburst and the problems in the current outburst prevention methods were analyzed. The main issues were pointed out such as the lack of regional outburst prevention measures, unsatisfactory effect in drainage, poor management and implementation, as well as personnel that need more training. The prevention situation of coal and gas outburst in Guizhou Province was considered. In accordance with the above problems, from the perspective of strengthening geological exploration, testing coal seam parameters, studying outburst prevention technologies, deploying mining systems rationally, improving mine safety management systems, and strengthening protection facilities and other aspects, a targeted outburst prevention measure and proposals were put forward.

关键词： coal and gas outburst prevention problem countermeasure

Synthesis of Hydroxystilbene Derivatives and their Antioxidant Activity by DPPH Method

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Chemical Research in Chinese Universities 2006年第6期22卷 742-746页

作者： li Yue-qing song Qi-ling CHEN Ping-ping ZHAO Wei-jie WANG Shi-sheng State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 P. R. China

Five hydroxystilbene derivatives were synthesized and their structures were determined using high-resolution mass spectrometry, ^1H NMB, and IR. In this study, the antioxidant activities of eight hydroxystilbenes （five synthesized hydroxystilbene derivatives and three other compounds） were evaluated with the free radiced scavenging model 1,1-diphenyl-2-picrylhydraxyl. It was observed that there exists a very significant linear rehtionship between the reciprocal of the EC50 value of each of the compounds and the maximum wavelength of the ultraviolet absorption peaks, It is believed that this result will be helpful for the further synthesis of such antioxidants.

关键词： Polyhydroxystilbene Antioxidant activity 1,1-Diphenyl-2-picrylhydrazyl (DPPH)

A simple analytical method for deflation prediction of inflatable structures

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Journal of Central South University 2015年第6期22卷 2277-2286页

作者：李庆松卿强龚景海 Department of Civil Engineering Shanghai Jiao Tong University

The static performance of inflatable structures has been well studied and the dynamic deployment simulation has received much attention. However, very few studies focus on its deflation behavior. Although there are several dynamic finite element algorithms that can be applied to the deflation simulation, their computation costs are expensive, especially for large scale structures. In this work, a simple method based on classic thermodynamics and the analytical relationship between air and membrane was proposed to efficiently analyze the air state variables under the condition of ventilation. Combined with failure analysis of static bearing capacity, a fast incremental analytical method was presented to predict both elastic and post wrinkling deflation process of inflatable structures. Comparisons between simplified analysis, dynamic finite element simulation, and a full-scale experimental test are presented and the suitability of this simple method for solving the air state and predicting the deflation behavior of inflatable structures is proved.

关键词： inflatable structure deflation wrinkling simulation control volume method

Pharmacokinetics and biodistribution of polymeric micelles of paclitaxel with Pluronic P123

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Acta Pharmacologica Sinica 2006年第6期27卷 747-753页

作者： li-mei HAN Jie GUO li-jun ZHANG qing-song WANG Xiao-ling FANG~2 Department of Pharmaceutics.School of Pharmacy,Fudan University,Shanghai 200032,China Department of Pharmaceutics School of Pharmacy Fudan University Shanghai China

Aim:To investigate the preparation,in vitro release,in vivo pharmacokineticsand tissue distribution of a novel polymeric micellar formulation of paclitaxel(PTX)with Pluronic ***:The polymeric micelles of paclitaxel with PluronicP123 were prepared by a solid dispersion *** characteristics of micellesincluding particle size distribution,morphology and in vitro release of PTX frommicelles were carried ***-loaded micellar solutions were administered throughthe tail vein to healthy Sprague-Dawley rats and Kunming strain mice to assessthe pharmacokinetics and tissue distribution of PTX,***,thecommercially available intravenous formulation of PTX,was also administered ***:By using a dynamic light scattering sizer and a transmissionelectron microscopy,it was shown that the PTX-loaded micelles had a mean sizeof approximately 25 nm with narrow size distribution and a spherical *** continuously released from Pluronic P 123 micelles in release medium contain-ing 1 mol/L sodium salicylate for 24 h at 37℃.In the pharmacokinetic assessment,t1/2βand AUC of micelle formulation were 2.3 and 2.9-fold higher than that of *** the PTX-loaded micelles increased the uptake of PTX in the plasma,ovary and uterus,lung,and kidney,but decreased uptake in the liver and brain inthe biodistribution ***:Polymeric micelles using Pluronic P123can effectively solubilize PTX,prolong blood circulation time and modify thebiodistribution of PTX.

关键词： paclitaxel micelle Pluronic P123 pharmacokinetics biodistribution

Study on the composite Nd:YAG crystal by laser micro-Raman spectroscopy

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Optoelectronics Letters 2007年第6期3卷 441-443页

作者： SUN Dun-lu ZHANG qing-li WAN song-ming JIANG Hai-he YIN Shao-tang Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences HeFei 230031 China

The composite Nd：YAG crystal with undoped YAG end caps was fabricated by thermal bonding technique. Scanning electron microscopy （SEM） result shows that the width of the bonded interface was about 0.5 lain. The laser micro-Raman was used to study the bonded interface of the composite crystal. The results of Raman spectra and the bonded interface image indicate that the undoped YAG and Nd：YAG crystals have been well bonded together. Furthermore, it can be drawn that the structure and the composition of the bonded interface are the same as the undoped YAG crystal, and that the Nd^3＋ ions do not enter the bonded interface and the YAG side. This property is advantageous to decrease the thermal effect of the boned interface and to improve the laser stability.

关键词：晶体生长 Nd:YAG 物理性质光谱激光

Studies on the Condensed Structure of Vacuum Cast Atactic Polystyrene Films

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Chemical Research in Chinese Universities 2000年第4期16卷 363-368页

作者： WANG You, HE Chu-ning and SHEN Jing-shu (Polymer Physics Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China) WU li-heng and song qing (China Textile Academy, Beijing 100025, China) 中科院化学所高分子物理及化学国家重点实验室北京 100080 中国纺织科学院北京 100025

The condensed structure of atactic-polystyrene (a - PS ) films cast from the solutions of differ- ent concentrations in dichloromethane under vacuum and atmospheric conditions was studied by differential scanning calorimetry(DSC). It was found that only under vacuum evaporating conditions did the endothermic peak in the DSC curves of a-PS films depend on the concentration of the a-PS solution. For the samples cast from the solution of concentration below 0. 010 g/mL, no endothermal peak was observed, but for those cast from the solution of concentration above 0. 020 g/mL, obvious endothermal peaks appeared. The onset of the endothermal peak is correlated with the critical overlapping concentration c' (0. 010-0. 020 g/mL), which is in agreement with the theoretically calculated one (Ccal=0.014 g/mL).

关键词： Differential scanning calorimeter(DSC) Critical overlapping concentration Atactic polystyrene film

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： song He li li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

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实际输入饱和的一类非完整运动学系统的镇定

控制理论与应用 2007年第6期24卷 909-912页

作者：刘毅王朝立李清松上海理工大学电气工程学院上海应用技术学院机械与自动化工程学院上海200235

对一类非完整移动机器人提出了实际输入饱和下镇定控制器的设计方案.这种设计不是基于链式系统而是基于原始系统的.控制器的设计使用了滑模控制和多步控制策略,并用Lyapunov的思想证明了闭环系统的收敛性.最后,用设计的控制器对一类机... 详细信息

对一类非完整移动机器人提出了实际输入饱和下镇定控制器的设计方案.这种设计不是基于链式系统而是基于原始系统的.控制器的设计使用了滑模控制和多步控制策略,并用Lyapunov的思想证明了闭环系统的收敛性.最后,用设计的控制器对一类机器人进行了仿真,验证了方法的有效性.

关键词：非完整控制系统镇定移动机器人输入饱和

基于提前支付的非瞬时变质产品批量订货定价策略

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控制与决策 2018年第2期33卷 301-308页

作者：曹裕李业梅李青松中南大学商学院长沙410083

当供应商处于供应链节点的买方市场时,通常要求零售商提前支付一定比例购置成本作为订金.针对该问题研究零售商促销努力下存在随机需求的非瞬时变质产品批量订货定价策略,考虑零售商提前支付策略,允许部分缺货.在一定条件下可得零售商... 详细信息

当供应商处于供应链节点的买方市场时,通常要求零售商提前支付一定比例购置成本作为订金.针对该问题研究零售商促销努力下存在随机需求的非瞬时变质产品批量订货定价策略,考虑零售商提前支付策略,允许部分缺货.在一定条件下可得零售商最优补货周期和局部最优定价策略,随之提出相应的求解算法.数值计算结果表明:若提前支付购置成本占比或利率增大,则零售商利润将显著减少;提前支付期限和期数均对最优利润产生消极影响;零售商采取积极促销策略可有效提升自身利润.

关键词：库存控制提前支付非瞬时变质产品随机需求