科创中国

在洪水计算中,河道糙率是一个重要参数.通过对河道糙率影响因素分析,利用李营水文试验站的实测资料,阐述了河道糙率的计算方法.糙率确定时影响因素较多,不同的水深、植被、河床等因素,都会对糙率值产生影响.在实际计算中,大部分设计河段没有实测糙率资料,在实际应用中要借助相似河道的参数代替,对计算精度影响较大.收集了国内外不同情况下的河道糙率实验资料,可供河道糙率计算参考.

Layered organic-inorganic hybrids containing bilayer perovsikte (R-NH3)2(CH3NH3)Pb2I7 (where R=C12H25,C6H5C2H4) were synthesized by reactions in solution. The influences of the solvents and the reactant ratio on the structures of the products were investigated. The structures and the properties of the hybrids were characterized using X-ray diffraction (XRD) and ultraviolet and visible (UV) adsorption spectra. For comparing with the bilayer perovskite hybrids in structure and band gap magnitude, the hybrids containing monolayer perovskite (R-NH3)2PbI4 were also synthesized and characterized. The results demonstrate that the thickness of inorganic layer has obvious effect on the tunneling magnitude of the band gap but the organic part can be micro actuator of band gap.

Dual mechanical port machine(DMPM), as a novel electromechanical energy conversion device, has attracted widespread attention. DMPM with spoke type permanent magnet arrangements(STPM-DMPM), which is one of several types of DMPM, has been of interest recently. The unique coupling characteristics of STPM-DMPM are beneficial to improving system performance, but these same characteristics increase the difficulties of control. Now there has been little research about the control of STPM-DMPM, and this has hindered its practical application. Based on a mathematical model of STPM-DMPM, the coupling characteristics and the merits and demerits of such devices are analyzed as applied to a hybrid system. The control strategies for improving the disadvantages and for utilizing the advantage of coupling are researched. In order to weaken the interaction effect of torque outputs in the inner motor and the outer motor that results from coupling in STPM-DMPM, a decoupling control method based on equivalent current control is proposed, and independent torque control for the inner motor and outer motor is achieved. In order to solve address the problem of adequately utilization of coupling, minimizing the overall copper loss of the inner motor and the outer motor of STPM-DMPM is taken as the optimization objective for optimal control, and the purpose of utilizing the coupling adequately and reasonably is achieved. The verification tests of the proposed decoupling control and optimal control strategies are carried out on a prototype STPM-DMPM, and the experimental results show that the interaction effect of torque outputs in the inner motor and the outer motor can be markedly weakened through use of the control method. The overall copper loss of the inner motor and the outer motor can be markedly reduced through use of the optimal control method, while the power output remains unchanged. A breakthrough in the control problem of STPM-DMPM is accomplished by combining the control methods. Good performance in the control of STPM-DMPM will enhance its practicality, particularly as applied to hybrid systems.

近年来,中国能源运输通道问题日益显现,以马六甲海峡及南海等区域最为突出.为解决我国能源通道安全受到严重制约的困局,利用因次分析法,依据评价指标体系建立的各项基本原则,针对出现的不同情况分别对传统运输通道与新路线做简要对比分析.在保证国内石油安全充足供应,尽可能降低物流成本的前提下,提出较为有效合理的对策和建议,对我国能源安全运输具有现实意义.

The identification of maximum road friction coefficient and optimal slip ratio is crucial to vehicle dynamics and control.However,it is always not easy to identify the maximum road friction coefficient with high robustness and good adaptability to various vehicle operating conditions.The existing investigations on robust identification of maximum road friction coefficient are unsatisfactory.In this paper,an identification approach based on road type recognition is proposed for the robust identification of maximum road friction coefficient and optimal slip ratio.The instantaneous road friction coefficient is estimated through the recursive least square with a forgetting factor method based on the single wheel model,and the estimated road friction coefficient and slip ratio are grouped in a set of samples in a small time interval before the current time,which are updated with time progressing.The current road type is recognized by comparing the samples of the estimated road friction coefficient with the standard road friction coefficient of each typical road,and the minimum statistical error is used as the recognition principle to improve identification robustness.Once the road type is recognized,the maximum road friction coefficient and optimal slip ratio are determined.The numerical simulation tests are conducted on two typical road friction conditions(single-friction and joint-friction)by using CarSim software.The test results show that there is little identification error between the identified maximum road friction coefficient and the pre-set value in CarSim.The proposed identification method has good robustness performance to external disturbances and good adaptability to various vehicle operating conditions and road variations,and the identification results can be used for the adjustment of vehicle active safety control strategies.

通过模拟水管式沉降仪埋设安装条件,按照监测规范及相关技术要求,结合水管式沉降仪测值计算及修正原理,对糯扎渡水电站水管式沉降仪模拟实验场地布置、材料要求、安装及坝料回填过程进行实验.监测数据结果表明,实验测点最大沉降分别为145 mm和37 mm,水管式沉降仪器整体测值稳定,波动变化较小,对于在糯扎渡高土石坝具有良好的适用性.

首先给出了若干标量Young型不等式.然后在此基础上,建立了相应的矩阵Young型不等式.

根据衡水市浅层地下水的水质监测资料,采用地下水环境质量标准,污染物主要有溶解性总固体、氨氮、锰、总硬度、硫酸盐、氟化物、高锰酸盐指数、氯化物等.综合污染指数总体呈下降趋势;并对硫酸盐、高锰酸盐指数、氨氮、锰主要污染物质进行变化趋势,受外界影响,其变化幅度较大.最后提出地下水保护措施和建议,为衡水市地下水资源合理开发利用提供参考依据.

经平绒是一种高档面料,在使用过程中易出现绒毛倒伏的现象,影响服饰美观.综合了针织"不倒绒"和机织长毛绒织物的特点,提出了用机织技术生产"不倒绒"经平绒机织面料的方法,阐述了原料选择、组织设计、固结方式选择、绒毛高度确定以及上机工艺参数设置等关键技术.研制的经平绒面料绒毛耸立,不易变形;面料光泽柔和,手感滑糯,弹性良好.

目的 观察养精胶囊对老年雄性SD大鼠性功能的影响,并探讨其可能的影响机制.方法 将40只老年雄性SD大鼠随机分为实验组和对照组,实验组给予养精胶囊(0.5g/kg·d-1)灌胃4周,对照组给予等剂量生理盐水灌胃相同时间.4周后通过观察两组大鼠阴茎勃起变化、检测血清睾酮水平和免疫组化方法检测大鼠阴茎海绵体组织中内皮型一氧化氮合酶(eNOS)及海绵体组织血管中CD34分子表达的变化情况等评价大鼠性功能变化情况.结果 (1)对照组老年大鼠干预后血清总睾酮水平较干预前下降,但组间比较差异无统计学意义(P>0.05);养精胶囊组老年大鼠干预后血清总睾酮水平较干预前有所提高,但差异亦无统计学意义(P>0.05);(2)在老年大鼠性功能指标方面:养精胶囊干预组老年大鼠阴茎勃起次数、勃起潜伏期及勃起维持时间均较对照组有所改善.(3)阴茎海绵体组织HE染色结果提示:养精胶囊组老年大鼠阴茎海绵体组织血管管腔明显扩张,充血,管腔内壁变薄;对照组老年大鼠阴茎海绵体组织内,血管管腔未见明显充盈扩张,管腔内充血不明显,且管腔有大量残留的陈旧性血液.(4)免疫组化结果提示:两组大鼠海绵体组织中,均可见深染的棕褐色阳性颗粒,但深染程度和颗粒分布密度不一.低倍镜(*100)视野下观察,药物干预后实验组大鼠阴茎海绵体组织中eNOS的阳性颗粒的数量明显高于对照组(P<0.05);(5)微血管密度结果提示:实验组老年大鼠阴茎海绵体组织血管内皮中CD34的表达明显强于对照组,高倍镜下(*400)观察,实验组微血管密度MVD值较对照组升高(P<0.05).结论 养精胶囊能促进血清睾酮的分泌,增强阴茎海绵体组织内eNOS的表达,这可能是养精胶囊改善大鼠性功能和阴茎勃起的作用机制.