mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
二次供水及市政直供水细菌学调查分析

为了解和评价二次供水的水质卫生状况,我们对信阳市卫生防疫站2001年6月～2003年6月所监测的城镇二次供水微生物指标进行统计分析,并与同时期集中式供水进行对比分析,参照近两年卫生监督机构相关调查资料,进行分析评价.实验室检验按照GB5750-1985<生活饮用水标准检验法>及<生活饮用水检验规范>(2001)进行.总大肠菌群用多管发酵法;菌落总数用平皿计数法;游离余氯采用邻苯甲胺比色法(永久性余氯比色溶液).现场采样及实验气检验均按标准化步骤进行.结果按<生活饮用水卫生规范>(2001)进行评价.
黄瓜花腐病的识别及防治

黄瓜花腐病多在保护地塑料大棚栽培的黄瓜上发生.该病在鞍山地区始见于20世纪90年代初.随着保护地种植黄瓜面积的不断扩大,发生的面积越来越大,该病危害有蔓延上升的趋势.因此,识别和防治黄瓜花腐病成为保护地黄瓜生产一个急需解决的问题.
"早大白"脱毒种薯级次与产量的关系

马铃薯品种"早大白"在阜新地区已成为主栽品种.但有些农户自行留种连续种植,致使种性退化严重,产量明显下降.2002年,我们采用"早大白"品种脱毒一级良种、二级良种、三级良种与当地农民的经多代生产的自留种薯进行了对比试验,观察马铃薯品种"早大白"脱毒种薯级次与产量的关系.
阜新地区春小麦春玉米间作高产栽培技术研究初报

近年来阜新地区春小麦春玉米间作发展较快,但米麦总产量水平还有待提高,为此,根据生产中存在的问题开展了米麦间作种植形式以及玉米品种筛选的研究,以确定适宜的玉米品种及合理的种植形式.
城市空气污染物与交通流量的关联度分析

目的探讨城市空气污染物与交通流量的关联度.方法在南宁市不同交通流量的街道进行空气采样,分析空气样品中NO2、SO2、CO、TSP浓度,并采用邓聚龙的灰色系统理论分析空气污染物浓度与交通流量的关联度.结果交通流量与SO2、NO2、CO、TSP的关联度分别为0.5764、0.6894、0.6817、0.7002,其中上述4种污染物与摩托车流量的关联度分别为0.6085、0.7290、0.7156和0.7144,与其他机动车流量的关联度分别为0.5220、0.6247、0.6051、0.6526.结论4种空气污染物浓度受交通流量影响的顺序为TSP＞NO2＞CO＞CO2,其中摩托车流量对上述4种空气污染物的影响最大.
脊髓栓系综合征的显微外科治疗

目的: 探讨采用显微神经外科技术治疗脊髓栓系综合征的方法和疗效. 方法: 回顾性分析1996-01/2002-08由我科同一手术组收治的76例脊髓栓系综合征患者的临床表现、病理学特征、显微外科治疗方法以及疗效. 结果: 本组术后在住院期间内(5～15 d)54例(71%)患者症状得到改善. 52例获得随访,在随访期内(0.5～7.0 a)治愈者占17%,显效46%,好转23%,无效13%,总有效率为86%;无严重并发症. 结论: 采用显微神经外科技术治疗脊髓栓系综合征可明显提高手术效果,对成年患者及首次手术未治愈的患者均应采取积极的手术治疗.
骨粒串主导的自由曲面变形算法

由于目前广泛应用的骨骼子空间变形算法本身固有的缺陷,常常导致生成的曲面出现"塌陷"与"萎缩",严重影响了生成曲面的真实感.提出一种骨粒串主导的自由曲面变形算法,通过重构曲面模型,将骨骼与曲面相结合,并把虚拟的骨骼实体化,成为可变形的骨粒串.变形时先计算每一骨粒的新坐标,然后计算相应皮肤顶点的新坐标.实验结果表明,该算法有效地消除了"塌陷"与"萎缩",生成的曲面具有高度真实感.
氮钙配施对番茄果实钾素含量及总积累量的影响

以沈阳草甸土为栽培基质,采用二次D-饱和最优设计,进行番茄N、Ca配施盆栽试验.探讨氮、钙配施对番茄果实钾素含量及钾素总积累量的影响.结果表明:在本试验条件下,N、Ca肥对番茄果实钾积累符合报酬递减律,N的效应远大于Ca.N、Ca交互呈微弱负效应;N、Ca肥配施对番茄钾素总积累量的二元二次回归方程为:Y=1716.939+6437.14 N+3041.66 Ca-8024.12N2-4866.21Ca2-2298.5 NCa.理论上若使番茄K素总积累量达到最大,需采用高氮低钙配施.
一种全差分的高速CMOS运算跨导放大器(OTA)的优化设计

全差分高速CMOS运算跨导放大器由一个折叠-级联输入级和一个共源输出增益级构成,并采用Cascode补偿技术.在对运算跨导放大器的性能做了详细的分析后,设计出一个采用单纯形优化算法的优化程序,它能够快速地设计出满足指标的运算跨导放大器.最后给出了一个设计实例.
Spin-glass-like behaviour and positive magnetoresistance in oxygen deficient La2/3Ca1/3MnO3-δ thin films

The magnetism and magnetoresistance (MR) in a series of oxygen-deficient La2/3Ca1/3MnO3-δ (LCMO) thin films have been investigated. Compared with the films with stoichiometric oxygen concentration, the oxygen-deficient LCMO thin films show a spin-glass-like behaviour at low temperatures and a positive MR effect above the metal–insulator transition temperature. The mechanism of such unusual phenomena is discussed.
On temporal evolution of precipitation probability of the Yangtze River delta in the last 50 years

The monthly precipitation observational data of the Yangtze River delta are transformed into the temporal evolution of precipitation probability (PP) and its hierarchically distributive characters have been revealed in this paper. Research results show that precipitation of the Yangtze River delta displays the interannual and interdecadal characters and the periods are all significant at a confidence level of more than 0.05. The interdecadal is an important time scale, because it is on the one hand a disturbance of long period changes and on the other hand it is also the background for interannual change. The interdecadal and 3–7y oscillations have different motion laws in the data-based mechanism self-memory model (DAMSM). Meanwhile, this paper also provides a new train of thought for dynamic modelling. Because this method only involves a certain length of data series, it can be used in many fields, such as meteorology, hydrology, seismology and economy etc and thus has a bright perspective in practical applications.
Development of 1.3GHz HTc rf SQUID

A new HTc rf SQUID working at around 1.3GHz has been developed to avoid electromagnetic interference such as growing mobile communication jamming. This new system works in a frequency range from 1.23 to 1.42GHz (centred at 1.3GHz), which is not occupied by commercial communication. The sensor used in the 1.3GHz rf SQUID is made of a HTc coplanar superconducting resonator and a large-area HTc superconducting film concentrator. We have achieved in the 1.3GHz HTc rf SQUID system a minimal flux noise of 2.5×10-5Φ0/(Hz)1/2 and a magnetic field sensitivity of 38fT/(Hz)1/2 in white noise range, respectively. The effective area of the concentrator fabricated on a 15×15mm2 substrate is 1.35mm2. It is shown that the 1.3GHz rf SQUID system has a high field sensitivity. Design and implementation of 1.3GHz HTc rf SQUID offers a promising direction of rf SQUID development for higher working frequency ranges.
Study of the surface and far fields of terahertz radiation generated by large-aperture photoconductive antennas

We have studied analytically the temporal characteristics of terahertz radiation emitted from a biased large-aperture photoconductive antenna triggered by an ultrashort optical pulse. We have included the effects of the finite lifetime and transient mobility dynamics of photogenerated carriers in the analysis. Succinct explicit expressions are obtained for the emitted radiation in the surface field and in the far field. The dependence of the waveforms of the radiated field on the fluence and duration of triggering optical pulse, carrier relaxation time and carrier lifetime are discussed in detail using the obtained expressions.
Second harmonic generation of propagating collective excitations in Bose–Einstein condensates

We consider a possible second harmonic generation (SHG) of propagating collective excitations in a two-component Bose–Einstein condensate (BEC) with repulsive atom–atom interactions. We show that the phase-matching condition for the SHG can be fulfilled if the wave vectors and frequencies of the excitations are chosen adequately from different dispersion branches. We solve the nonlinear amplitude equations for the SHG derived using a method of multiple-scales and provide SHG solutions similar to those obtained for a SHG in nonlinear optical media. A possible experimental realization of the SHG for the propagating collective modes in a cigar-shaped two-component BEC is also discussed.
Experimental investigation of the impact on nearby solid boundary during laser-generated bubble collapse

Cavitation damage has been considered as being responsible for many effects in hydraulic machinery and biological medicine. In order to better understand the cavity interaction with nearby solid surfaces, the impact loading induced by the high-speed liquid-jet and subsequent jet flow during the final stage of the bubble collapse in a static fluid is investigated by focusing a Q-switched pulsed laser into water. By means of a new method based on a fibre-coupling optical beam deflection technique, a detailed experimental study has been made to clarify the relationship of the impact pressure against a solid boundary as a function of the dimensionless γ that is generally used to describe the bubble dynamics with its definition γ = s/Rmax (Rmax being the maximum bubble radius and s denoting the distance of the cavity inception from the boundary). The experimental results are shown that for γ in the range of about 0.67 to 0.95 with a pulsed laser energy 230mJ, the transient pressure applied on the solid surface is maximum; while for γ>1 or γ<0.67, it is gradually decreased. By combination of our experimental results with the other work that detected the acoustic emission during the bubble collapse at different γ, it is concluded that in this range of 0.67–0.95, the destructive effect due to a liquid-jet and the following jet flow impact actually outweighs the well-known effect of shock wave emission and plays a vital role during the cavitation bubble collapse.
Intein-mediated Rapid Purification of Recombinant Human Pituitary Adenylate Cyclase Activating Polypeptide

In order to obtain the recombinant human PACAP efficiently by intein-mediated single column purification, a gene encoding human PACAP was synthesized and cloned into Escherichia coli expression vector pKYB. The recombinant vector pKY-PAC was transferred into E. coli ER2566 cells and the target protein was over-expressed as a fusion to the N-terminus of a self-cleavable affinity tag. After the PACAPintein-CBD fusion protein was purified by chitin-affinity chromatography, the self-cleavage activity of the intein was induced by DTT and the rhPACAP was released from the chitin-bound intein tag. The activity of the rhPACAP to stimulate cyclic AMP accumulation was detected using the human pancreas carcinoma cells SW1990. Twenty-two milligrams of rhPACAP with the purity over 98% was obtained by single column purification from 1 liter of induced culture. The preliminary biological assay indicated that the rhPACAP, which has an extra Met at its N-terminus compared with the native human PACAP, had the similar activity of stimulating cAMP accumulation with the standard PACAP38 in the SW1990 cells. A new efficient production procedure of the active recombinant human PACAP was established.
Mid-infrared generation based on a periodically poled LiNbO3 optical parametric oscillator

We report a nanosecond Nd:YVO4-pumped optical parametric oscillator (OPO) based on periodically poled LiNbO3 (PPLN). Tuning is achieved in this experiment by varying the temperature and period of the PPLN. The design of double-pass singly resonant oscillator (DSRO) and confocal cavity enables the OPO threshold to be lowered considerably, resulting in a simple, compact, all-solid-state configuration with the mid-infrared idler powers of up to 466mW at 3.41μm
Ground state properties of a Bose–Einstein condensate confined in an anharmonic external potential

In light of the interference experiment of Bose–Einstein condensates, we present an anharmonic external potential model to study ground state properties of Bose–Einstein condensates. The ground state energy and the chemical potential have been analytically obtained, which are lower than those in harmonic trap. Additionally, it is found that the anharmonic strength of the external potential has an important effect on density and velocity distributions of the ground state for the Thomas–Fermi model.
Synthesis and electrochemical properties of nanocrystalline Li[Li1/3Ti5/3O4] by complex sol-gel method

Li[Li1/3 Ti5/3 O4] spinel-framework structure material is a kind of great interest for negative electrodes in energy storage cell. The synthesis of nanocrystalline Li[Li1/3 Ti5/3 O4] by sol-gel method using inorganic compounds and citric acid is developed, and single phase powder is obtained above 700 ℃. The electrochemical performances of Li[Li1/3Ti5/3O4] cathodes in lithium cell are studied. Special capacities are 131 mA · h · g-1 at 0.5C rate and 154 mA · h · g-1 at 0.1C in cycle test. No passivation layer is formed on Li[Li1/3Ti5/3O4] anode in lithium ion battery, and it is much safer than lithium metal and carbonaceous anodes. Faradic impedance in the charged cell is remarkably higher than that in discharged state, which is caused by distinct conductivities of Li [ Li1/3 Ti5/3 O4 ] and Li2 [Li1/3 Ti5/3 O4 ].
Mechanism of extracting palladium(Ⅱ) with cyclic sulfoxide derivatives

The extraction ability of palladium( Ⅱ ) from acidic media with cyclic sulfoxide derivatives-α-Dodecyl-tetrahydrothiophene 1-Oxide (DTMSO), α-octyl-tetrahydrothiophene 1-Oxide (OTMSO) and α-butyl-tetrahydro-thiophene-1-Oxide (BTMSO) was investigated. The extracting efficiency of cyclic sulfoxide derivatives decreased with the increasing of acidity in the lower acidity, and the efficiency became stable with the change of acidity in the higher acidity. The extraction reaction of palladium( Ⅱ )with DTMSO is exothermic, and extraction reaction of pal-ladium( Ⅱ ) is endothermic when OTMSO or BTMSO were used as extracting reagents. The coordination number was studied by slope method. The results indicate that coordination number is 2, and the composition of complex is Pd is coordinated with both oxygen and sulfur atom in S=O group in sulfoxide derivatives.
Distribution behavior of Copper and Tin between FeO-rich slag and iron solution

The distribution behavior of residual elements copper and tin between FeO-rich slag and iron solution was investigated under the condition of an induction furnace. The results indicate that a part of copper and tin is incidently oxidized when oxygen is blasted into bath to react with iron element. The distribution ratio of copper and tin between slag and metal is about 0.1. Phenomena of Cu and Sn elements segregation and accumulation in slag were observed by means of EPMA analysis. The distribution ratio of copper and tin between slag and metal may descend with increasing of CaO content in slag.
Effects of pH value of reaction solution on structure and electrochemical performance of calcium-containing active material of secondary zinc electrodes

The calcium-containing active material of secondary alkaline zinc electrodes was prepared by a chemical coprecipitation method and characterized by scanning electron microscopy(SEM) and X-ray diffractometry(XRD).Their electrochemical performance was tested by the Galvanstatic charge-discharge method. The experimental results show that the sample synthesized at pH = 11.15 has a typical calcium zincate crystal. The zinc electrode using this sample as active material shows higher discharge capacity, more negative discharge plateau potential and longer cycle lifetime.
Purification and Characterization of Cold-active α-Amylase Excreted by A Strain of Marine Cold-adaptive Penicillia

The filamentous fungi from the Huanghai sea sludge were screened according to their ability to produce cold-active α-amylase. The strain with the highest amylase activity was identified as Penicillium species. The α-amylase purified by ammonium sulphate precipitation and column chromatography on DEAE-sepharose and sephadex G-100 shows a molecular weight of about 55000 and a pI of 4.38. The enzyme is stable in a pH range of 5.5-8.0 and has a maximum activity at pH 6.0. Compared with the α-amylase from mesophiles and thermophiles, the cold-active enzyme shows a high enzyme activity at lower temperatures and a high sensitivity at temperatures higher than 50 ℃. The optimal temperature is 40 ℃ and the activity decreases dramatically at temperatures above 50 ℃. Ca2+ shows a significant effect on maintaining the structure and the activity of the enzyme. EDTA and Cu2+ are its inhibitors. The products from the hydrolysis of soluble starch with the cold-active enzyme are maltose and other oligosaccharides.
Construction of Hybrid Enzyme from HEC-SOD and Cu,Zn-SOD

Human extracellular superoxide dismutase(hEC-SOD) is a secreted tetrameric protein involved in the protection of a human body from oxygen free radicals. Its three-dimensional structure has not been confirmed. hEC-SOD couldn′t be expressed in E.coli. We constructed a hybrid enzyme, which comprises the N-terminal and C-terminal domains from hEC-SOD, fused it to human Cu,Zn-SOD. The hybrid enzyme is expressed successfully in E.coli. Further, we analyzed the expression of hEC-SOD in E.coli by mRNA differential displaying.
Dual-frequency IP over Tanghuping Prospect

Gold mineralization in the Tanghuping Prospect was the target of the geophysical exploration. The mineralization shows close relation with geological structures and is accompanied by alteration. Sulfide concentrations in the altered zones were used to trace the mineralization by Induced Polarization(IP) method. Through laboratory and field measurements of some selected samples of the study area, their geophysical properties were studied carefully.After that by numerical calculation, a geophysical model was built. Six lines were designed to use dual-frequency IP sounding in the west of the surveyed area. Gradient, pole-dipole and reverse pole-dipole arrays were used to acquire the data. Interpretation of the processed data shows eight veins that demonstrate diverging and converging phenomena. Therefore east of the surveyed area is considered as most prosperous zone in the study area.
XPS characteristics of sulfur of bio-oxidized arsenic-bearing gold concentrate and changes of surface nature of bio-oxidation residue

During bio-oxidation of sulfides, the chemical state change of sulfur is a complex and key factor. It is not only an indicator of the extent and intensity of the bio-oxidation, but also controls the property of bio-leaching medium and the period of oxidation. The chemical state of sulfur in sulfides oxidized by leaching bacteria was studied with XPS. Sulfide minerals in the arsenic-hearing gold concentrate consist of pyrite, arsenopyrite, chalcopyrite, galena, sphalerite and so on. In order to probe the pattern of the chemical state change of sulfur in the bio-oxidation residue of arsenic-bearing gold concentrate, the structure of the grains, and the surface nature of the residue, XPS test was carried out through different sputtering duration. The study of XPS clearly shows that: sulfides is progressively oxidized from the surface of minerals to the core by leaching bacteria; the chemical valence of sulfur changes from S2- or [S2]2- to [SO4]2-; sulfur in the core is in a reduction state, S2- or [S2]2- , but exists in an oxidation state S6+ on the surface; due to the chemical state change of sulfur, mineral phase of the bio-oxidation residue is also changed(sulfides inside, while sulfates outside); the layered structure is found in the grains of the bio-oxidation residue.
Intelligent temperature control system of quench furnace

A fuzzy-neural networks intelligent temperature control system of quench furnace was presented. Combined genetic algorithm with back-propagation algorithm, the weight values of neural networks, parameters of fuzzy membership functions and inference rules can be adjusted automatically, which realizes the optimal control of temperature. The results show that this control system can run effectively with satisfied temperature precision: in temperature uprising stage, overshot of temperature is under 4 ℃; in stable stage, the scope of temperature change is controlled within ±2 ℃, which meets the need of control veracity of temperature.
Tribological behavior of three typical bearing alloys under influence of additives

The influences of lubricating additives on the tribological behavior of lead, tin, copper base bearing alloys-0.45 %C steel rubbing pairs under the condition of boundary lubrication were researched. The results show that because of the difference of physical chemistry performance at bearing alloys and steel, some conventional lubricating additives which is beneficial to steel-steel rubbing pairs is harmful to these bearing alloys-steel rubbing pairs, and the wear volume can be increase by 7 times under the test condition. The measure results of contact resistance during the test process show that the higher the contact resistance at rubbing surface, the better the tribological behavior of tribo-system. Moreover for the lead base and tin base bearing alloys-0.45%C steel rubbed pairs, the thicker the compact oxide layer of steel surface, the larger the friction coefficient and wear volume, which demonstrates that oxidation wear plays an important part in the wear process.
Electrochemical flotation of ethyl xanthate-pyrrhotite system

The flotation behavior of pyrrhotite was investigated by using ethyl xanthate as a collector. The results show that pyrrhotite has good floatability from pH 2 to 11, and poor flotability when pH＞12. The reagents adjusting potential are ammonium persulfate ((NH4)2 S2 O8) and sodium dithionite (Na2 S2O4 ). The flotation of pyrrhotite is dependent on pulp potential at certain pH value. The potential-pH range for pyrrhotite flotation was established. Cyclic voltammetry and FTIR spectroscopy analysis show that the major adsorption product of ethyl xanthate on pyrrhotite is dixanthogen. The intensity of FTIR signals of dixanthogen adsorbed on pyrrhotite and the anode current of a pyrrhotite electrode and flotation response of pyrrhotite are correlated with pulp potentials.
Warm compacting behavior of stainless steel powders

The warm compacting behaviors of four different kinds of stainless steel powders, 304L, 316L, 410L and 430L, were studied. The results show that warm compaction can be applied to stainless steel powders. The green densities and strengths of compacts obtained through warm compaction are generally higher than those obtained through cold compaction. The compacting behaviors in warm compaction and cold compaction are similar.Under the compacting pressure of 700 MPa, the warm compacted densities are 0. 10 - 0.22 g/cm3 higher than the cold compacted ones, and the green strengths are 11.5 %-50 % higher. The optimal warm compacting temperature is 100 - 110 ℃. In the die wall lubricated warm compaction, the optimum internal lubricant content is 0.2%.
Influences of sub-micrometer Ta and Co dopants on microstructure and properties of tungsten heavy alloys

Tungsten heavy alloys are aggregates of particles of tungsten bonded with Ni/Fe or Ni/Cu via liquidphase sintering. The sub-micrometer Ta Co powder was added to this aggregate to strengthen the bonding phase. It is found that the main fracture pattern of the alloys is cleavage of tungsten grains and ductile rupture of bond phase,leading to improved tensile strength and elongation. Dopant Ta can act as grain size inhibitor in tungsten heavy alloys.
Microstructure of Al2O3/SiO2 ceramic core nano-composites

Al2O3/SiO2 ceramic core nano-composites were prepared and their microstructure was investigated by transmission electron microscope(TEM). The results show that intergranular nano-composites are achieved. The bonding between Al2O3 and SiO2 particles is well and the interface is even. Amorphous phases and nano crystals appear in the Al2O3/SiO2 ceramic core nano-composites, which both come into being during the cooling process after sintering. Glass phase does not appear between the Al2O3 and SiO2 particles and only appears among the Al2O3 particles, which can be explained with stress model. The quantity of the glass phase is not much and its influence on the high-temperature deformation of the ceramic core nano-composites is little.
Ceramic bonding and joint's strengthening through forming intermetallic compounds in situ

The transient liquid phase diffusion bonding of Si3 N4 ceramics with Ti/Ni/Ti and Al/Ti/Al multiple interlayers was performed. The formation of intermetallic compounds in situ and their effects on the joints' strengths were investigated. The Ti/Ni/Ti interlayers produce NiTi and Ni3 Ti layers with considerable room temperature ductility and high elevated temperature strength to strengthen the bonding zone metals and the joints. The joints with 142 MPa shear strength at room temperature and 88 MPa shear strength at 800 ℃ are achieved under appropriate parameters, respectively. Al/Ti/Al interlayers transform into a special bonding zone metal with a large amount of Al3Ti particles and a small amount of Al-based solid solution, and in this case, the joints are strengthened significantly. Their strengths at room temperature and 600 ℃ reach 90 MPa and 30 MPa, respectively.
Solitary Wave and Wave Front as Viewed From Curvature

The solitary wave and wave front are two important behaviors of nonlinear evolution equations. Geometri cally, solitary wave and wave front are all plane curve. In this paper, they can be represented in terms of curvature c(s), which varies with arc length s. For solitary wave when s →±∞, then its curvature c(s) approaches zero, and when s = 0, the curvature c(s) reaches its maximum. For wave front, when s →±∞, then its curvature c(s) approaches zero, and when s = 0, the curvature c(s) is still zero, but c'(s) ≠ 0. That is, s = 0 is a turning point. When c(s) is given, the variance at some point (x, y) in stream line with arc length s satisfies a 2-order linear variable-coefficient ordinary differential equation. From this equation, it can be determined qualitatively whether the given curvature is a solitary wave or wave front.