Study on the Electrical Conductivity of Au Nanoparticle/Chloroform and Toluene Suspensions

Au nanoparticles capped by hexadecanethiol and dodecanethiol were chemically synthesized. The characteristics of electrical conductivity for the capped nanoparticles dissolved in chloroform and toluene solvents were investigated. The electrical conductivity of the samples is conspicuously Au nanoparticle concentration dependent. The results show that a rapid conductivity increases when the nanoparticle concentration increases from low value to a moderate value of 5.47 g/L and 11.22 g/L, which is capped by hexadecanethiol and dodecanethiol in chloroform solvent, and 2.77 g/L and 7.88 g/L in toluene solvent. The room-temperature dc conductivity σ dc of Au nanoparticle capped by hexadecanethiol is smaller than that capped by dodecanethiol in the whole range of Au nanoparticle concentrations. The conductivity of Au nanoparticle suspensions increases almost linearly in the temperature range in above two solvents.

Tao, Virtue, Benevolence, Righteousness and Propriety:On the Core Values of Shu School

The core concepts of Confucianism were developed over the change of the times by Confucian scholars after Zi Si and Mencius, and have formed their respective structures: The three great principles of "benevolence, wisdom and bravery," and the self-cultivation model of "benevolence, righteousness and propriety" by Confucius. Following Confucius, Zi Si vigorously advocated the five virtues of "benevolence, righteousness, propriety, wisdom and sage."Mencius initiated the four cardinal virtues of "benevolence, righteousness, propriety and wisdom."Xun Zi often constructed the collocation of "benevolence and righteousness, rites and music, and loyalty and trustworthiness."Dong Zhongshu finally developed the five constant virtues of "benevolence, righteousness, propriety, wisdom, and trustworthiness."In a simple, clear, practical and feasible way, the core values of Confucianism have won support among the people and have had an impact on Chinese society for more than two thousand years. Being open and inclusive, the connotation of Confucianism took advantage of the strengths of different schools of philosophy in ancient China, and adopted changes from philosophies with positive attitudes. The Bashu area, in the southwest of China, has inherited the tradition of adhering to the Tao(natural order of the Universe) and valuing morality. Shu scholars have creatively built the core values of "the Tao, virtue, benevolence, righteousness and propriety," and developed a characteristic branch of philosophy above and beyond the Confucian scholars of the Central Plains. This concept stems from Yan Junping of the Western Han Dynasty, promoted by Yang Xiong, developed by Zhao Rui of the Tang Dynasty, Zhang Shangying and Su Dongpo of the Song Dynasty, and Lai Zhide of the Ming Dynasty, then further developed by Liu Yuan and Duan Zhengyuan of the Qing Dynasty, and formed the persistent system of core values of the Shu School. Compared with the values of orthodox Confucianism, the core values of the Shu School have the functions of"a unity of metaphysics and physics"and"a combination of theory and practice,"which remedy the lack of Confucianism's ultimate concern for ontology and the lack of Taoism's realistic concern for practicality.

Seasonal Changes in Photosynthetic Characteristics of Ammopiptanthus mongolicus

Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductance and stomatal limitation value tended to decline simultaneously, while the interoellularCO2 concentration was increased. According to the two criteria discriminating the stomatal limitation of Photosynthesis suggeSted by Fmrquhar and Sharkey, the seasonal changes in these parameters indicated that the decrease in Pn may not be due to stomatal factor. These studies proved that the relative contents of the large subunit of Rubisco and the photochemical activities correlated with the seasonal changes in the net photosyntheticrate, whieh may show that these two factors contribute primarily to the seasonal changeS in CO2 assimilation.

Correlation Analysis of Two Hydrochemical Factors Affecting the Distribution of Ceratopteris thalictroides in China

[ Objective] This study was to analyze the two hydrochemical factors affecting the distribution of Ceratopteris thalictroides, further to provide basis for its habitat protection and population restoration. [ Method ] Twenty two hydrochemical parameters of 22 sampling sites in China＇s tropical and subtropical zones were respectively averaged for calculating their variation coefficients, of which the two showing significant differences were used for multiple comparisons and correlation analyses via least significant difference and correlation coefficient. E Result ] The correlation coefficients of all the 22 tested hydrochemical parameters varied hugely, but only pH value and conductivity showed significantly differences in two water body （type A and type B）. Analysis of correlation presented that pH value were positively correlated with conductivity; further the multiple comparisons showed that the significant difference of pH value was higher than that of conductivity. [Conclusion] With regard to the two hydrochemical parameters showing significant differences, pH value influences the distribution of C. thalictroides more.

Enhancing thermoelectric performance of p-type SnTe through manipulating energy band structures and decreasing electronic thermal conductivity

SnTe has received considerable attention as an environmentally friendly alternative to the representative thermoelectric material of PbTe.However,excessive hole carrier concentration in SnTe results in an extremely low Seebeck coefficient and high thermal conductivity,which makes it exhibit relatively inferior thermoelectric properties.In this work,the thermoelectric performance of p-type SnTe is enhanced through regulating its energy band structures and reducing its electronic thermal conductivity by combining Bi doping with CdSe alloying.First,the carrier concentration of SnTe is successfully suppressed via Bi doping,which significantly decreases the electronic thermal conductivity.Then,the convergence and flattening of the valence bands by alloying CdSe effectively improves the effective mass of SnTe while restraining its carrier mobility.Finally,a maximum figure of merit(ZT) of~ 0.87 at 823 K and an average ZT of~ 0.51 at 300-823 K have been achieved in Sn_(0.96)Bi_(0.04)Te-5%CdSe.Our results indicate that decreasing the electronic thermal conductivity is an effective means of improving the performance of thermoelectric materials with a high carrier concentration.

Reconstruct the Heat Conduction Model with Memory Dependent Derivative

The classical heat conduction equation is derived from the assumption that the temperature increases immediately after heat transfer, but the increase of temperature is a slow process, so the memory-dependent heat conduction model has been reconstructed. Numerical results show that the solution of the initial boundary value problem of the new model is similar to that of the classical heat conduction equation, but its propagation speed is slower than that of the latter. In addition, the propagation speed of the former is also affected by time delay and kernel function.

BLOW－UP AND DIE－OUT OF SOLUTIONS OF NONLINEAR PSEUDO-HYPERBOLIC EQUATIONS OF GENERALIZED NERVE CONDUCTION TYPE

This paper considers the initial boundary value problems with three types of the boundary conditions for nonlinear pseudo-hyperbolic equations of generalized nerve conduction type, using foe eigenfunction method, the conditions for which the solutions blow-up and die-out in the finile time are got.

Quantum Conductance Staircase of Edge Hole Channels in Silicon Quantum Wells

We present the findings for the quantum conductance staircase of holes that is caused by the edge channels in the ultra-shallow p-type silicon quantum well (Si-QW), 2 nm, confined by the δ-barriers heavily doped with boron on the n-type Si (100) surface. This longitudinal quantum conductance staircase, Gxx, is revealed by the voltage applied to the Hall contacts, Vxy, to a maximum of 4e2/h. In addition to the standard plateau, 2e2/h, the variations of the Vxy voltage appear to exhibit the fractional forms of the quantum conductance staircase with the plateaus and steps that bring into correlation respectively with the odd and even fractional values.

基于价值传导视角的科技人才评价改革机制研究

科技人才评价具有价值导向作用,反映了国家的价值认知。研究发现,目前中国对科技创新的价值认知已发生变化,新的价值导向集中体现为“四个面向”。当前科技人才评价改革取得了一定成效,但在转变价值导向方面尚未破题。改革的深层逻辑是建立以新的创新价值认知为基础的评价价值导向,这不仅是评价方式方法上的优化或评价内容的调整,而是一次系统性的变革。同时,研究提出科技创新价值传导的两条路径,即基于政策制定落实的直接路径和基于科技资源配置的间接路径,分析从国家科技创新价值认知到科技项目、机构、人才计划和奖励、基地平台、学科学位等评估评价评审工作,再到科技人才微观评价的价值传导逻辑与转化机制。最后,从构建一个开放多元的科技人才评价体系角度,提出未来应进一步围绕“改政府”“放主体”“强社会”“立文化”展开的“四元”改革建议。

基于POD降维外推差分算法的热传导模型研究

针对一维热传导问题,基于奇异值分解和特征投影本征分解(proper orthogonal decomposition,POD)法通过提取特征模态,建立了一种极少自由度、较高精度的降维外推仿真模型。给出模型降维近似解分量的数学推导、算法过程以及误差分析,实现了温度场的快速计算。最后,通过数值例子,将POD计算结果与有限差分法(FDM)计算结果进行了对比。结果表明:POD方法在不同的时间步长、空间步长及定解条件下,均能捕捉到传热过程的准确信息,平均计算速度比传统有限差分法计算速度提高了200倍,有效缩短了计算机模拟时间。考核了低阶模型的准确性,并说明了低阶方程可以定性的反映原高维系统的传热特性。同时,POD所得结果与FDM结果间的最大相对误差为0.15%,满足工程计算精度要求。所提出的POD降维外推算法方案,不但扩展了POD特征空间,而且可以逐步改进数值求解步骤,弥补了POD方法的不足,验证了利用POD降维算法研究传热问题的可行性与有效性。对于实现复杂传热模型的高效准确的分析与仿真数值求解过程有一定的理论参考价值。

在线活细胞定量检测模型的建立及其在辅酶Q10中的应用

在类球红细菌发酵生产辅酶Q10的过程中,其菌体生长代谢情况及产物合成与有活力的细胞量密切相关。活细胞传感仪通过利用细胞的介电特性,能够检测发酵液中的活细胞量,且检测结果不受死细胞、气泡的影响。在辅酶Q10的发酵过程中,运用活细胞传感仪采用全频扫描模式对检测到的电容值进行校正,校正后的电容值与CFU具有良好的线性关系,R^(2)=0.995,可以准确预测发酵液中菌体生长状态和活细胞量。基于电导率和校正后的电容值对辅酶Q10发酵过程中补料策略进行优化,辅酶Q10产量最终达到3420 mg/L。

不同温度对偏高水分玉米储藏品质变化规律的影响

偏高水分玉米储藏难度大,品质劣变速度快,严格控制适当的储藏温度有利于延缓其品质劣变,提高其储藏品质。该试验选择水分含量为14.5%的玉米作为偏高水分玉米样品,将其在不同温度下储藏6个月,探究低温(15℃)、准低温(20℃)、常温(25℃)和高温(30℃)等不同温度对偏高水分玉米储藏品质的影响。结果表明,偏高水分玉米在15、20℃下储藏6个月之后,品质保持良好;25℃下储藏6个月时,其色泽、生活力、发芽势、发芽率均发生了不同程度地下降,玉米粉轻微老化,脂肪酸值为51.88 mg/100 g,呈宜存状态;30℃下储藏6个月时,其色泽、生活力、发芽势、发芽率均剧烈下降,电导率迅速增加,玉米粉老化程度严重,脂肪酸值增至84.05 mg/100 g,呈重度不宜存状态。根据上述品质指标综合评价,建议粮库选择20℃储藏偏高水分(14.5%)玉米,可在保证玉米储藏品质的同时有效提高经济效益。

一种CE102 能力验证方法及实例

文章给出了一种多样品并行传递的CE102能力验证方法及实例,自主研发并制备47套均匀性、稳定性符合要求的能力验证样品,在40家参加实验室中并行分发该样品,相比传统的单样品轮流传递的方式,极大缩短了测试时间,且消除了无备用样品带来的风险。使用稳健算法计算稳健平均值并将其作为指定值,使用GB/T 6113.402-2018中给出的测量不确定度计算能力评定标准差,并将其用于评价参加实验室是否离群。最后对离群的原因进行了分析并提出了改进意见。

高低碳碳化稻壳保温性能研究

针对碳化稻壳的蜂窝状结构还是碳含量是其起保温作用的情况,采用自主设计的测无定形隔热材料导热系数装置,测得C35型碳化稻壳(含碳量≥35%)与普通低碳碳化稻壳(含碳量≤15%)导热系数比为0.87~0.94。计算碳化稻壳燃烧放热量同钢水或钢渣通过碳化稻壳层散热量,发现前者是后者的约47~295倍,碳含量为碳化稻壳起保温作用的主要因素。经实践,钢包中加入厚度2.4 cm的碳化稻壳,保温时间约为8~10 min。综合比较使用高碳碳化稻壳保温的性价比更高。

求解一类平行四边形域上热传导反问题的无网格方法

基于基本解和径向基函数相结合的方法,对采用不同径向基作为近似解的基底,用平行四边形域反演一类热传导反问题的初值和热源项进行研究.因插值构造的方程系数矩阵是病态的,即系数矩阵的条件数较大,本文基于GCV准则的奇异值分解正则化方法求解线性方程组,选取不同噪声级,通过数值算例显示所给方法是稳定有效的.

梁漱溟与笛卡尔的“身、心”二元论对比分析研究——兼论东西方文化交流互鉴中的中国境域

梁漱溟早期文化“三路向”说中的“身、心”二元论虽取材于笛卡尔,却不拘囿于本体论和认识论的视域,其以笛卡尔的二元论为参照,虽在理论构型的立场、目标、元点上实现了对西方传统理性主义的反转,突破了传统“天人合一”的旧有范式,构建了以传统儒家人伦为基础的价值本体论,推动了近代中华传统文化的生存转向和现代性转型。但是,梁漱溟以“心”为本所创生的“善恶”的形而上学依据,在结构主义的对比分析视角下存在严重的价值论困境和模糊的现实指向。文章旨在批判性考察梁漱溟“身、心”二元论困境,揭示出遮蔽在困境背后有益的东西方文化交流通路,以兹为当代坚守中国文化、返本开新提供侧面参考意蕴。

Persistent and advanced reddening of sweetgum leaves after major veins severing

The effects of major veins severing on morphological and physiological features of sweetgum （Liquidambar styraciflua L.） leaves were investigated by observing leaf color change and measuring leaf temperature, green/luminance （G/L） value of half-lobes, leaf stomata conductance, and water content in Yamaguchi University, Japan. The palmately veined leaves of sweetgum （Liquidambar styraciflua L.） were found more sensitive to the major vein severing than that of other species Major veins severing resulted in serious water stresses, as indicated by the persistent reddening and/or advanced reddening of local leaf, lower leaf stomatal conductance, and higher leaf temperature, etc. Severed leaf can be clearly divided into non-severed area, transitional area, and stressed area, which the three areas have different colours and temperature. The major vein barrier can also be seen clearly. The persistent reddening and advanced reddening seem consistent with the phenomenon of red crown top of some sweetgum trees and may have similar mechanism.

基于图像处理的弓网参数检测方法

针对目前铁路受电弓静态拉出值与导高值检测效率低、误差较大等问题,提出一种基于实时图像处理的动态拉出值、导高值的测量方法。首先,对相机进行标定,得到像素值和实际值的对应关系,通过固定的相机获取受电弓位置,利用形状匹配算法得到受电弓具体位置参数;其次,利用Hough直线检测算法得到受电弓上边缘直线;再次,通过线条宽度的判别和最小二乘法拟合得到接触线;最后,计算出接触线和受电弓上边缘直线的交点坐标,结合相机标定参数,进而得到实际的拉出值和导高值。

空心玻璃微珠对加成型有机硅灌封胶硫化性能的影响

通过不同方式对空心玻璃微珠填料表面进行处理,检测了填料滤液的pH值和电导率。利用有机硅灌封胶在硫化过程中黏度翻倍时间和失粘时间的变化趋势,研究了不同处理方式得到的空心玻璃微珠对有机硅灌封胶硫化性能的影响。实验结果表明:当硅乙烯基与硅氢物质的量比为1∶1时,加成型有机硅灌封胶硫化时间合适;不同处理方式的空心玻璃微珠滤液的pH值变化不大,但电导率差异明显;空心玻璃微珠的处理方式对有机硅灌封胶硫化性能和存放稳定性的影响差异也较大。其中,经乙烯基三甲氧基硅烷、γ-(2,3-环氧丙氧)丙基三甲氧基硅烷、UM08处理后的微珠,其表面因杂质被有效去除或包裹,对加成型有机硅灌封胶的硫化性能和贮存稳定性影响较小。

黄陵矿区地热特征与煤热共采前景分析

为研究黄陵矿区地热地质特征及地热资源开发利用,整理和研究了黄陵矿区85个煤孔测井井温资料,梳理测温孔在48~72 h的近似稳态测温数据,编制了有代表性测温孔孔底温度曲线,同时计算了矿区地温梯度,绘制了黄陵矿区地温梯度特征分布图,并在此基础上绘制了500、1000、1500 m垂深地温分布特征图。同时,结合采集的岩石热导率测试数据,计算出黄陵矿区的大地热流值,并对地热资源进行了评估。研究结果表明,黄陵矿区测温钻孔井底温度恢复与井内稳定时间之间呈指数函数关系,以此建立了温测钻孔井底温度变化的校正公式;黄陵矿区主要地热参数为地温梯度在1.1~5.2℃/hm之间,平均值为2.7℃/hm;500 m垂深平均地温为24.99℃,1000 m垂深为38.53℃,1500 m垂深为52.07℃;岩石热导率为2.0~4.0 W/(m·K),在3.0~3.5 W/(m·K)时最多,平均值为2.54 W/(m·K);大地热流值为32.71~97.62 mW/m^(2),平均值为63.17 mW/m^(2);在平面上,地温梯度、地温场、大地热流总体呈现为南高北低、东高西低的分布趋势。基于黄陵矿区地热资源评估,矿区的热储层地热资源量为3.11×10^(19)J,可采热能储量为4.65×10^(18)J。目前黄陵矿区煤热共采地热利用多集中在矿井余热,考虑到黄陵矿区优异的地热赋存及矿井开采条件,进一步开展煤-热共采地热利用技术的研究及工程示范具有重要的示范意义。