接地电阻测量回路中辅助电极位置的变化规律

针对测量接地电阻时通常采用的三电极法所存在的不足,提出增加辅助电流极的个数,用多电极法测量接地电阻.从三电极法出发,导出了四电极、五电极、六电极、八电极法及任意电极法测量接地电阻时电位过零点、误差补偿点的表达式,并通过计算得出了随着电流极数目的增加电位过零点和误差补偿点的位置的变化规律.以四电极、六电极法为例,用电解槽模拟试验证明了理论分析和计算的正确性.     

SCI收录全军区10所总医院1997-2005年学术论文计量分析

以SCIE为数据源,对全军10所总医院近9年科技论文被SCI收录的数量情况进行了统计分析,并在此基础上,进一步对南京总医院近年来发表论文的科室分布情况以及与国内外合作情况进行了统计分析,并以南京总医院近9年来科研的特点及规律为例,为全军各总医院今后的科研规划与发展提出了一些建议。     

Quantum Information Entropies on Hyperbolic Single Potential Wells

In this work, we study the quantum information entropies for two different types of hyperbolic single potential wells. We first study the behaviors of the moving particle subject to two different hyperbolic potential wells through focusing on their wave functions. The shapes of these hyperbolic potentials are similar, but we notice that their momentum entropy densities change along with the width of each potential and the magnitude of position entropy density decreases when the momentum entropy magnitude increases. On the other hand, we illustrate the behaviors of their position and momentum entropy densities. Finally, we show the variation of position and momentum entropies Sx and Sp with the change of the potential well depth u and verify that their sum still satisfies the BBM inequality relation.     

Unveiling the Hidden Therapeutic Potential of Carnosine,a Molecule with a Multimodal Mechanism of Action: A Position Paper

Carnosine (β-alanyl-L-histidine) is a naturally occurring endogenous dipeptide and an over-the-counter food supplement with a well-demonstrated multimodal mechanism of action that includes the detoxification of reactive oxygen and nitrogen species, the down-regulation of the production of pro-inflammatory mediators, the inhibition of aberrant protein formation, and the modulation of cells in the peripheral (macrophages) and brain (microglia) immune systems. Since its discovery more than 100 years ago, a plethora of in vivo preclinical studies have been carried out; however, there is still substantial heterogeneity regarding the route of administration, the dosage, the duration of the treatment, and the animal model selected, underlining the urgent need for “coordinated/aligned” preclinical studies laying the foundations for well-defined future clinical trials. The main aim of the present position paper is to critically and concisely consider these key points and open a discussion on the possible “alignment” for future studies, with the goal of validating the full therapeutic potential of this intriguing molecule.     

预测模型组合开关

不同预测模型在同一时刻都存在不同的预测误差,最优组合预测的预测精度要比其他模型高,但并不是所有时刻误差都最小,有的时刻可能比单项预测误差还大,因此,在预测时就存在较大的风险.再组合预测可以降低预测风险,但方法比较复杂难以推广.针对这些问题,我们设计一种预测模型组合开关,根据数据的变化,不同时刻采用不同预测模型,使预测误差每一期都最小,或不是最大.实证结果表明,预测模型开关能够根据数据特征有效控制模型输出.     

Interplay Between Quark-Antiquark and Diquark Condensates in Vacuum in a Two-Flavor Nambu-Jona-Lasinio Model

By means of a relativistic effective potential, we analytically research competition between the quark- antiquark condensates （qq） and the diquark condensates （qq） in vacuum in ground state of a two-flavor Nambu Jona Lasinio （NJL） model and obtain the Gs-Hs phase diagram, where Gs and Hs are the respective four-fermion coupling constants in scalar quark-antiquark channel and scalar color anti-triplet diquark channel. The results show that, in the chiral limit, there is only the pure （qq） phase when Gs/Hs 〉 2/3, and as Gs/Hs decreases to 2/3 〉 Gs/Hs ≥ 0 one will first have a coexistence phase of the condensates （qq） and （qq） and then a pure （qq） phase. In non-zero bare quark mass case, the critical value of Gs/Hs at which the pure （qq） phase will transfer to the coexistence phase of the condensates （qq） and （qq） will be less than 2/3. Our theoretical results, combined with present phenomenological fact that there is no diquark condensates in the vacuum of QCD, will also impose a real restriction to any given two-flavor NJL model which is intended to simulate QCD, i.e. in such model the resulting sma/lest ratio Gs/Hs after the Fierz transformations in the Hartree approximation must be larger than 2/3. A few phenomenological QCD-like NJL models are checked and analyzed.     

Positions and Widths of Anticrossings for Potassium Rydberg Stark States

The B-spline expansion technique is applied to study the anticrossings for potassium Rydberg states in a static electric field. The results of our calculation indicate that the antierossings are caused mainly by the core interaction or by the fine structure interaction. Our results for the positions and the widths of the anticrossings are in good agreement with experimental data.     

Wave Damping over a Perforated Plate with Water Chambers

Introduction In recent decades,various permeable structures have been used in coastal engineering projects not only as breakwaters to prevent wave attacks but also as sea-walls to dissipate harbor waves.Permeable structures can be cataloged by their appea…     

矩阵电位滴定法批量同时测量丙酮酸生产中钙镁的含量

探讨了矩阵电位滴定法在不经分离的情况下测量钙镁含量的测量原理、方法和误差影响因素,并用该法对丙酮酸生产过程中,中间产品的钙镁离子含量进行测量,RSD(%)=2.01(Ca),RSD(%)=0.31(Mg)。     

Effect of Bauhinia monandra Kurz Leaf Preparations on Embryonic Stages and Adult Snails of Biomphalaria glabrata (Say, 1818), Schistosoma mansoni Cercariae and Toxicity in Artemia salina

Biomphalaria glabrata snails constitute the main vector of schistosomiasis in Brazil, and Bauhinia monandra Kurz, the leaves of which contain BmoLL lectin with biocidal action, is a plant widely found on continents in which the disease is endemic. This work describes the composition of B. monandra preparations and the effect on embryos and adult snails, their reproduction parameters and hemocytes. We also describe the results of a comet assay after B. glabrata exposure to sublethal concentrations of the preparations. Additionally, the effects of the preparations on S. mansoni cercariae and environmental monitoring with Artemia salina are described. In the chemical evaluation, cinnamic, flavonoid and saponin derivatives were detected in the two preparations assessed, namely the saline extract and the fraction. Both preparations were toxic to embryos in the blastula, gastrula, trochophore, veliger and hippo stages (LC₅₀ of 0.042 and 0.0478; 0.0417 and 0.0419; 0.0897 and 0.1582; 0.3734 and 0.0974; 0.397 and 0.0970 mg/mL, respectively) and to adult snails (LC₅₀ of 6.6 and 0.87 mg/mL, respectively), which were reproductively affected with decreased egg deposition. In blood cell analysis, characteristic cells for apoptosis, micronucleus and binucleation were detected, while for comet analysis, different degrees of nuclear damage were detected. The fraction was able to cause total mortality of the cercariae and did not present environmental toxicity. Therefore, B. monandra preparations are promising in combating schistosomiasis since they can control both the intermediate host and eliminate the infectious agent, besides being safe to the environment.