摘要：In order to create low temperature environment for the valve testing,a new type of semiconductor refrigeration box based on semiconductor refrigeration chip and programmable logic controller(PLC)control system is *** power of the semiconductor refrigeration chip is determined by calculating the heat dissipation characteristics of the semiconductor refrigeration *** natural convection heat dissipation with forced air cooling,the heat sink of semiconductor refrigeration chip is *** the control strategy,switch control is combined with an intelligent control *** single neuron optimization algorithm based on quadratic optimization is adopted to adjust and optimize the parameters of the proportional-integral-derivative(PID)controllers in real *** into account the limited hardware capabilities of the PLC,the Jacobian information in parameter adjustment is redesigned into a simplified form of *** actual test results of refrigeration box show good control performance.

摘要：针对方捆机喂入易堵塞、作业效率低的问题,使用SolidWorks软件设计一种双喂入叉式喂入机构。运用SolidWorks Motion软件对喂入机构进行运动仿真分析,获得并分析喂入叉端点的运动轨迹及速度变化趋势,确认喂入机构的结构设计满足喂入要求;运用SolidWorks Simulation软件对喂入机构进行静力学和模态仿真分析,结果表明,喂入主轴的最大应力为565 MPa,连杆最大应力为293 MPa,小于材料的屈服强度,喂入机构强度满足要求;喂入机构固有模态最低频率(一阶模态)为67.127 Hz,与喂入机构工作频率1.67 Hz,发动机激励频率18 Hz均不相等,喂入机构不会发生共振,喂入机构模态满足要求。田间试验表明,方捆机的生产率为8.7 t/h,成捆率为99.4%,秸秆草捆密度为125.6 kg/m3。

摘要：开封东大寺有河南首坊之称,是开封创建年代较早、规模最大的清真寺,2006年被列为第六批全国重点文物保护单位。该文在文献查找、实地调研和测绘研究的基础上,通过梳理东大寺的历史沿革,分析其空间格局、建筑形制和装饰艺术等,归纳其空间组织的特征,探析得知东大寺体现了伊斯兰教与中国文化的有机融合,是中原地区清真寺本土化的鲜活实例。

摘要：Due to the increasing global demand for industrial gas, the development of large-scale cryogenic air separation systems has attracted considerable attention in recent years. Increasing the height of the adsorption bed in a vertical radial flow adsorber used in cryogenic air separation systems may efficiently increase the treatment capacity of the air in the adsorber. However, uniformity of the flow distribution of the air inside the adsorber would be deteriorated using the height-increasing method. In order to reduce the non-uniformity of the flow distribution caused by the excessive height of adsorption bed in a vertical radial flow adsorber, a novel parallel connection method is proposed in the present work. The experimental apparatus is designed and constructed; the Computational Fluid Dynamics(CFD) technique is used to develop a CFD-based model, which is used to analyze the flow distribution, the static pressure drop and the radial velocity in the newly designed adsorber. In addition, the geometric parameters of annular flow channels and the adsorption bed thickness of the upper unit in the parallelconnected vertical radial flow adsorber are optimized, so that the upper and lower adsorption units could be penetrated by air simultaneously. Comparisons are made between the height-increasing method and the parallel connection method with the same adsorber height. It is shown that using the parallel connection method could reduce the difference between the maximum and minimum radial static pressure drop by 86.2% and improve the uniformity by 80% compared with those of using the height-increasing method. The optimal thickness ratio of the upper and lower adsorption units is obtained as 0.966, in which case the upper and lower adsorption units could be penetrated by air simultaneously, so that the adsorbents in adsorption space could be used more efficiently.

摘要：Considering that hydrogen peroxide(H2O2)plays significant roles in oxidative stress,the cellular signal transduction and essential biological process regulation,the detection and imaging of H2O2 in living systems undertakes critical ***,we have developed a novel two-photon fluorescence turn on probe,named as Pyp-B for mitochondria H2O2 detection in living *** studies show that probe Pyp-B exhibit highly sensitive response toward H2O2 than other reactive oxygen species(ROS)and reactive nitrogen species(RNS)as well as biologically relevant *** fluorescence colocalization studies demonstrate that the probe can localize in the mitochondria ***,as a bio-compatibility molecule,the highly selective and sensitive of fluorescence probe Pyp-B have been confirmed by its cell imaging application of H2O2 in living A549 cells and zebrafishes under the physiological conditions.

摘要：Regulation of osteogenic differentiation of bone mesenchymal stromal cells （BMSCs） plays a critical role in bone regeneration. As small non-coding RNAs, microRNAs （miRNAs） play an important role in stem cell differentiation through regulating target-mRNA expression. Unfortunately, highly efficient and safe delivery of miRNAs to BMSCs to regulate their osteogenic differentiation remains challenging. Conventional inorganic nanocrystals have shown increased toxicity owing to their larger size precluding renal clearance. Here, we developed novel, surface-engineered, ultra-small gold nanoparticles （USAuNPs, 〈10 nm） for use as highly efficient miR-5106-delivery systems to enable regulation of BMSC differentiation. We exploited the effects of AuNPs coated layer-by-layer with polyethylenimine （PEI） and liposomes （Lipo） to enhance miR-5106-delivery activity and subsequent BMSC differentiation capacity. The PEI- and Lipo-coated AuNPs （Au@PEI@Lipo） showed negligible cytotoxicity, good miRNA-5106-binding affinity, highly efficient delivery of miRNAs to BMSCs, and long-term miRNA expression （21 days）. Additionally, compared with commercial Lipofectamine 3000 and 25 kD PEI, the optimized Au@PEI@Lipo-miR-5106 nanocomplexes significantly enhanced BMSC differentiation into osteoblast-like cells through activation of the Sox9 transcription factor. Our findings reveal a promising strategy for the rational design of ultra-small inorganic nanoparticles as highly efficient miRNA-delivery platforms for tissue regeneration and disease therapy.

摘要：在电子商务背景下,以Drop-shipping模式下的一个两级供应链为研究对象,着重探索供应商的经营决策。在这种模式下,电子零售商主要负责产品的宣传和销售工作,并将订单传递给供应商,由供应商完成生产和配送。但是由于电子商务的复杂性,供应商并不能对零售商的广告信息进行全面掌握,故供应商需要考虑如何通过制定批发价格来激励零售商的广告行为。基于Stackelberg博弈模型,研究供应商(领导者)在面临零售商(跟随者)不对称的广告信息时如何制定产品的批发价格和配送水平,以及电子零售商的广告策略。最后,通过仿真模拟的方法探讨了各决策主体的利润变化规律以及供应链的协调和优化策略。

摘要：鸟虫书是春秋战国时流行于吴、越、楚、蔡、宋、徐等地的一种特殊书体,它于春秋战国时期在青铜器、玺印、砖甓、瓦当上得到了广泛的运用,在春秋战国时代鸟虫书就分为两种基本装饰体类型:具象意味浓厚的装饰书体和抽象简便的书体。先秦时期,鸟虫篆保留了大量的具象符号,但到了汉代,鸟虫书不再做具象的摹拟,而是以其富有屈曲生动的笔画来充实空间,表现书体的装饰美感。它同时表现出了曲线美,流动美,极有个性,对于当今的艺术创作具有十分重要的指导意义。

摘要：《建筑地基基础设计规范》(GB 50007—2002)首次提出地基基础设计等级概念,并主要以此界定地基基础变形验算的范围,体现了地基基础设计按变形控制的原则,但也存在一些误解以及与相关技术标准矛盾等问题。在对地基基础设计等级的来源、演变过程、确定依据等论述的基础上,综合阐释了地基基础设计等级的作用与功能,并分析了地基基础设计等级与现行相关规范的协调问题,论述可对工程技术人员理解规范有所帮助。

摘要：中国古代建筑多为土木结构,火灾发生频率高。因此,防火功能是建筑设计与营造的重要考量。在考古遗址或历史文献中均可见到建筑防火设施的设计与营造,主要体现为:在墙体附壁柱或在室内木柱上涂泥、白灰或特制的防火涂料;以瓦顶取代茅草顶,以夯土或砖墙代替木骨泥墙;在相对密集的城市建筑之间开辟防火巷、营造防火墙;城门木门外涂泥或包以铁皮,城门洞上部设计注水灭火设施以便在木质城门被火烧时能及时扑灭;根据“厌火”观念,在屋脊两端设计鸱吻,以及在室内顶部设计出藻井。此外,古人还营造了水井、望火楼等消防设施。