mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Theoretical Investigations of the Physical Properties of Cd1?_xCa_xO Ternary Alloys

The structural, electronic and thermodynamic properties of Cd1?_xCa_xO ternary alloys are calculated using the first principles calculations performed within the framework of density functional theory.The exchange correlation potential for structural properties is calculated by the standard generalized gradient approximation(GGA)of Perdew et al., while for the electronic properties, the modified Becke-Johnson(MBJ)scheme is also applied.A deviation of the lattice constants from Vegard‘s law and bulk modulus from linear concentration dependence(LCD)are observed for the alloys.In addition, the thermodynamic stability of the alloys is investigated by calculating the critical temperatures of alloys.
Effect of Wavefront Properties on Numerical Aperture of Fresnel Hologram in Incoherent Holographic Microscopy

Fresnel incoherent correlation holographic(FINCH)microscopy is a recently developed new technique, which employs a spatial light modulator(SLM)as the beam splitter.Light originating from the same object point is split into two beams by the wavefront-division phase mask displayed on SLM, and a Fresnel-zone plate-like hologram is formed by the interference of the two beams.The numerical aperture NA_H of the recorded Fresnel hologram is introduced as a comprehensive parameter for evaluating the imaging characteristics in the FINCH scheme.The effect of wavefront properties on NA_H of the hologram is investigated theoretically in the sense of optimizing imaging resolution.The variation trends of NA_H are described and an optimal NA_H is achieved by implementing an appropriate phase mask for a given recording distance between SLM and CCD;thus optimized imaging resolution and signal-to-noise ratio are demonstrated experimentally.
对《~(131)I治疗格雷夫斯甲亢指南(2013版)》有关问题的解答

2013年4月《~(131)I治疗格雷夫斯甲亢指南(2013版)》(简称《指南》)发表。《指南》由中华医学会核医学分会组织的编写委员会在2010年发表的《~(131)I治疗Graves甲亢专家共识(2010年)》基础上,吸收近年来国外出版的甲状腺疾病指南、权威教科书、循证医学文献的精华,结合我国~(131)I治疗格雷夫斯甲亢的研究进展和临床实践总结编写而成,力求既适应临床工作的需求,又反映本领域当前最新进展,从而进一步规范和提高我国~(131)I治疗格雷夫斯甲亢的临床诊治水平。《指南》包括42个问题、52条推荐,共计33千字,引用了77条参考文献。因《指南》涵盖内容较多,且部分参考国外相关文献,为帮助读者更好地理解与掌握,笔者现对《指南》中的有关问题解答如下。
显微支撑喉镜下摘除声门下-颈段气管多形性腺瘤1例

多形性腺瘤是多发于颌面部腺体组织的常见良性肿瘤,但位于声门下-颈段气管的多形性腺瘤少见报道。我科于2012年7月收治1例声门下-颈段气管交界处多形性腺瘤患者,并行显微支撑喉镜下肿瘤摘除,随访1年,报道如下。1临床资料患者,女,56岁。因“体检时发现气管新生物3 d”入院。患者体检时行颈椎侧位片检查提示“气管新生物”(图1),进一步颈胸部CT检查提示声门下-颈段气管交界处前壁偏左侧结节状新生物,胸部CT平扫未见明显异常(图2)。呼吸内科行支气管镜检查提示声门下约1.5 cm处前壁偏左侧结节状红色新生物,表面有少量新鲜出血,大小约0.5 cm×0.8 cm×0.9 cm,阻塞部分管腔,支气管镜未进一步深入(图3)。转我科住院治疗后,详细追问病史,患者否认气促、咯血、咳嗽、咳痰、声嘶、畏寒、发热等症状,自觉平时生活、劳动未受影响。完善检查后,局麻下偏低位做气管切开术(约4~5环处),经此造瘘口插管全麻,施行显微支撑喉镜下肿瘤摘除术:选择略窄的喉镜,并在插入时让喉镜前端部分进入声门下,充分暴露声门下-颈段气管肿瘤,固定。分离肿瘤操作前,在肿瘤以下气管插管以上放置盐水纱条,以保护气管插管及气囊,手术结束时取出。在显微镜下利用喉显微器械从肿瘤较窄的基底部周边锐性分离肿瘤,并完整摘除肿瘤,出血不多,创面用盐酸肾上腺素棉球压迫后,单极电凝烧灼止血。术后抗感染,雾化吸入,对症等治疗。术后常规病理证实为多形性腺瘤(图4)。经试验性堵管成功后,术后第5天拔除气管套管,术后第8天气管切开处愈合,无呼吸困难。随访12个月,未见气促、咯血、声嘶等异常,无新生物复发。目前仍在随访中。
11例异位胰腺的临床诊治分析

目的探讨异位胰腺的诊断与治疗方法。方法回顾性分析该院2008年1月至2013年1月收集的11例异位胰腺患者的临床资料。病变位于胃贲门部1例,胃底2例,胃体2例,幽门窦5例,十二指肠球部及降段多发1例;10例为单发,1例为多发。结果异位胰腺诊断通过临床表现及影像学检查有一定的难度,11例患者经手术治疗后,患者症状完全缓解,预后好,未出现复发及其相关的病情恶化表现。随访3~60个月,患者一般状况较好,无消化道不适症状,复查胃镜检查未见异常。结论对有临床表现的异位胰腺患者必需行手术治疗;若无症状的患者,一经诊断为异位胰腺,最好手术治疗。
2013年第八届国际病理学会亚太地区学术大会简介

病理诊断的重要性通过几个关键环节得以不断提升,最近的环节就是“个性化医学”对病理诊断和病理学家的挑战,病理学既是一门传统的学科,又在不断引进新的技术。2013年9月5至8日第八届国际病理学会亚太地区学术大会在韩国釜山市召开,本次会议的主题是“病理学,开启个性化医学(pathology,opening the personalized medicine)”。来自亚太地区47个国家和地区的千余名代表参加了本次大会,除了亚洲和太平洋沿岸国家和地区外,还有欧洲的一些国家,如丹麦、瑞典、瑞士、德国、捷克、英国,以及非洲一些国家,如埃及、喀麦隆等国也有代表参加了会议,亚太病理学会议已经发展成为全球性的国际会议。中国包括大陆、香港、台湾地区20余位专家到会,南京大学医学院附属鼓楼医院孟凡青教授、北京友谊医院周小鸽教授、第四军医大学王哲教授被选在会上作报告。大会包括6次全体会议(即专题报告),19个论坛(114人发言)、14个病例读片讨论会(110人发言)、471份壁报展示。
腹部钝伤致孤立性胆总管完全横断一例

讨论外伤性肝外胆道损伤者仅占所有腹部损伤的3% ~5%,多为锐性穿透伤所致,常同时合并肝脏、胰腺等其他腹腔脏器的损伤,由钝性伤所致者较为少见。而钝性伤所致孤立性胆总管完全横断伤更为罕见。查阅国内文献,仅报道7例腹部钝性伤致胆总管横断,7例均合并有其他脏器损伤。其中1例表现为出血性休克,影像学提示膈下游离气体;4例表现为腹腔出血伴腹膜炎;其余2例未列出具体临床表现。7例均具备剖腹探查指征,胆道损伤均为术中诊断。外伤性胆道损伤发生机制复杂,分析本例患者受伤机制,患者被快速飞起的石块击中右上腹后,右侧肋弓受到强烈挤压,肝脏被动上移,而十二指肠及胰腺位置相对固定,因此导致胆总管走行人胰腺处强烈撕扯发生完全横断。本例患者因未合并其他脏器损伤,受伤之初腹部B超及CT均未显示明显异常,且胆汁局限于后腹膜,无明显腹膜炎体征,故更易漏诊、误诊。因此,我们认为对于右上腹外伤后诊断不明时,除考虑腹部其他脏器损伤外,还应考虑孤立性胆总管损伤可能,常规行腹部增强CT或MRCP有利于诊断。治疗方面,如考虑肝外胆道损伤,应果断行剖腹探查。对于全身情况良好,局部坏死较轻的患者,我们主张一期行胆总管空肠吻合,以保证胆道引流通畅,避免发生胆道狭窄。对于合并出血、感染重、坏死组织多者应遵循损伤控制性手术原则,先行胆道外引流,二期再行胆道重建手术。
InAs/GaAs far infrared quantum ring inter-subband photodetector

In this paper, we presented a numerical analysis of absorption coefficient, dark current and specific detectivity for InAs/GaAs quantum ring inter-subband photodetector (QRIP). 3D Schrodinger equation was solved using finite difference method and based on effective mass approximation. Dimensions of quantum ring (QR) were considered that inter-subband transition was to be accomplished for radiations of 20 μm. Resonant tunneling (RT) barriers were designed with tunneling probability of unity for electrons with energy of 0.062 meV to lower dark current of conventional QRIP. Numerical analyses show that inclusion of RT barriers can reduce dark current for about two orders of magnitude. Furthermore, specific detectivities for conventional QRIP and RT-QRIP were calculated respectively, and results at different temperatures were compared. It is suggested that specific detectivity for RT-QRIP is one order of magnitude higher than that for conventional QRIP. It is suggested that RT barriers considerably improve the specific detectivity of conventional QRIP at different temperatures.
Modelling of a tubular solid oxide fuel cell with different designs of indirect internal reformer

The cell performance and temperature gradient of a tubular solid oxide fuel cell with indirect internal reformer (IIR-SOFC) fuelled by natural gas, containing a typical catalytic packed-bed reformer, a catalytic coated wall reformer, a catalytic annular reformer, and a novel catalytic annular-coated wall reformer were investigated with an aim to determine the most efficient internal reformer system. Among the four reformer designs, IIR-SOFC containing an annular-coated wall reformer exhibited the highest performance in terms of cell power density (0.67 W·cm~(-2)) and electrical efficiency (68%) with an acceptable temperature gradient and a moderate pressure drop across the reformer (3.53×10~(-5) kPa). IIR-SOFC with an annular-coated wall reformer was then studied over a range of operating conditions: inlet fuel temperature, operating pressure, steam to carbon (S : C) ratio, gas flow pattern (co-flow and counter-flow pattern), and natural gas compositions. The simulation results showed that the temperature gradient across the reformer could not be decreased using a lower fuel inlet temperature (1223 K--1173 K) and both the power density and electrical efficiency of the cell also decreased by lowering fuel inlet temperature. Operating in higher pressure mode (1-10 bar) improved the temperature gradient and cell performance. Increasing the S : C ratio from 2 : 1 to 4 : 1 could decrease the temperature drop across the reformer but also decrease the cell performance. The average temperature gradient was higher and smoother in IIR-SOFC under a co-flow pattern than that under a counter-flow pattern, leading to lower overpotential and higher cell performance. Natural gas compositions significantly affected the cell performance and temperature gradient. Natural gas containing lower methane content provided smoother temperature gradient in the system but showed lower power density and electrical efficiency.
Novel Ni/CeO_2-Al_2O_3 composite catalysts synthesized by one-step citric acid complex and their performance in catalytic partial oxidation of methane

A series of novel Ni/CeO_2-Al_2O_3 composite catalysts were synthesized by one-step citric acid complex method. The as-synthesized catalysts were characterized by N_2 physical adsorption/desorption, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, hydrogen temperature-programmed reduction (H_2-TPR), X-ray photoelectron spectroscopy (XPS) and thermogravimetry analysis (TGA). The effects of nickel content, calcination and reaction temperatures, gas hourly space velocity (GHSV) and inert gas dilution of N_2 on their performance of catalytic partial oxidation of methane (CPOM) were investigated. Catalytic activity test results show that the highest methane conversion (>85%), the best selectivities to carbon monoxide (>87%) and to hydrogen (>95%), the excellent stability and perfect H_2/CO ratio (2.0) can be obtained over Ni/CeO_2-Al_2O_3 with 8 wt% Ni content calcined at 700 ℃ under the reaction condition of 750 ℃, CH_4/O_2 ratio of 2 : 1 and gas hourly space velocity of 12000 mL·h~(-1)·g~(-1). Characterization results show that the good catalytic performance of this composite catalyst can be contributed to its large specific surface area (~108 m~2·g~(-1)), small crystallite size, easy reducibility and low coking rate.
Simulation analysis of combined UV/blue photodetector in CMOS process by technology computer-aided design

A composite ultraviolet (UV)/blue photodetector structure has been proposed, which is composed of P-type silicon substrate, P_(well), N_(well) and N-channel metaloxide- semiconductor field-effect transistor (NMOSFET) realized in the P_(well). In this photodetector, lateral ringshaped P_(well)-N_(well) junction was used to separate the photogenerated carriers, and non-equilibrium excess hole was injected to the P_(well) bulk for changing the bulk potential and shifting the NMOSFET’s threshold voltage as well as the output drain current. By technology computer-aided design (TCAD) device, simulation and analysis of this proposed photodetector were carried out. Simulation results show that the combined photodetector has enhanced responsivity to UV/blue spectrum. Moreover, it exhibits very high sensitivity to weak and especially ultral-weak optical light. A sensitivity of 7000 A/W was obtained when an incident optical power of 0.01 μW was illuminated to the photodetector, which is 35000 times higher than the responsivity of a conventional silicon-based UV photodiode (usually is about 0.2 A/W). As a result, this proposed combined photodetector has great potential values for UV applications.
Texturization and rounded process of silicon wafers for heterojunction with intrinsic thin-layer solar cells

Heterojunction with intrinsic thin-layer (HIT) solar cells are sensitive to interface state density. Traditional texture process for silicon solar cells is not suitable for HIT one. Thus, sodium hydroxide (NaOH), isopropanol (IPA) and mixed additive were tentatively introduced for the texturization of HIT solar cells in this study. Then, a mixture including nitric acid (HNO_3), hydrofluoric acid (HF) and glacial acetic acid (CH_3COOH) was employed to round pyramid structure. The morphology of textured surface and the influence of etching time on surface reflectance were studied, and the relationship between etching time and surface reflectance, vertex angle of pyramid structure was analyzed. It was found that the mixture consisting of 1.1 wt% NaOH, 3 vol% IPA and 0.3 vol% additives with etching time of 22.5 min is the best for HIT solar cells under the condition of 80°C. Uniform pyramid structure was observed and the base width of pyramid was about 2–4 μm. The average surface reflectance was 11.68%. Finally the effect of different processes on the performance of HIT solar cells was investigated. It was shown that these texturization and rounding techniques used in this study can increase short circuit current (J_(sc)), but they have little influence on fill factor (FF) and open circuit voltage (V_(oc)) of HIT solar cells.
Vanadium metabolism investigation using substance flow and scenario analysis

Vanadium is a vital strategic resource, and vanadium metabolism is an important part of the national socio-economic system of China. This study conducts accounting and scenario analysis on the life cycle of vanadium metabolism in China. Based on the characteristics of vanadium life cycle and substance flow analysis (SFA) framework, we present a quantitative evaluation of a static anthropogenic vanadium life cycle for the year 2010. Results show that anthropogenic vanadium consumption, stocks, and new domestic scrap are at 98.2, 21.2, and 4.1 kt, respectively; new scrap is usually discarded. The overall utilization ratio of vanadium is 32.2%. A large amount of vanadium is stockpiled into tailings, debris, slags, and other spent solids. A scenario analysis was conducted to analyze the future developmental trend of vanadium metabolism in China based on the SFA framework and the qualitative analysis of technology advancement and socio-economic development. The baseline year was set as 2010. Several indicators were proposed to simulate different scenarios from 2010 to 2030. The scenario analysis indicates that the next 20 years is a critical period for the vanadium industry in China. This paper discusses relevant policies that contribute to the improvement of sustainable vanadium utilization in China.
Using crosslinked polyvinyl alcohol polymer membrane as a separator in the microbial fuel cell

Separator between anode and cathode is an essential part of the microbial fuel cell (MFC) and its property could significantly influence the system performance. In this study we used polyvinyl alcohol (PVA) polymer membrane crosslinked with sulfosuccinic acid (SSA) as a new separator for the MFC. The highest power density of 759±4mW?m~(-2) was obtained when MFC using the PVA membrane crosslinked with 15% of SSA due to its desirable proton conductivity (5.16 ×10~(-2) S?cm~(-1)). The power density significantly increased to 1106 ± 30 mW?m~(-2) with a separator-electrode-assembly configuration, which was comparable with glass fiber (1170± 46 mW?m~(-2)). The coulombic efficiencies of the MFCs with crosslinked PVA membranes ranged from 36.3% to 45.7% at a fix external resistance of 1000 Ω. The crosslinked PVA membrane could be a promising alternative to separator materials for constructing practical MFC system.
Macroeconomic impacts of oil price volatility: mitigation and resilience

Dependency on oil-derived fuels in various sectors, most notably in mobility, has left the global economy vulnerable to several macroeconomic economic side effects. Numerous studies have addressed the effect of price volatility on specific economic parameters. However, the current literature lacks a comprehensive review of the interactions between global macroeconomic performance and oil price volatility (OPV). Price volatility is intrinsic in commodity markets, but has been advancing at a faster rate in the crude oil market in comparison to other commodities over the past decade, reflecting the status of oil as the most globalised commodity. In this paper, the analytical literature review and analysis of the behavioral responses of macroeconomic agents to OPV shows that such volatility has several damaging and destabilizing macroeconomic impacts that will present a fundamental barrier to future sustainable economic growth if left unchecked. To ensure macroeconomic isolation from OPV, a combination of supply and demand-side policies have been recommended that can help to mitigate and build resilience to the economic uncertainty advanced by OPV.
Thermal buckling behavior of laminated composite plates: a finite-element study

In this paper, the thermal buckling behavior of composite laminated plates under a uniform temperature distribution is studied. A finite element of four nodes and 32 degrees of freedom (DOF), previously developed for the bending and mechanical buckling of laminated composite plates, is extended to investigate the thermal buckling behavior of laminated composite plates. Based upon the classical plate theory, the present finite element is a combination of a linear isoparametric membrane element and a high precision rectangular Hermitian element. The numerical implementation of the present finite element allowed the comparison of the numerical obtained results with results obtained from the literature: 1) with element of the same order, 2) the first order shear deformation theory, 3) the high order shear deformation theory and 4) the threedimensional solution. It was found that the obtained results were very close to the reference results and the proposed element offers a good convergence speed. Furthermore, a parametrical study was also conducted to investigate the effect of the anisotropy of composite materials on the critical buckling temperature of laminated plates. The study showed that: 1) the critical buckling temperature generally decreases with the increasing of the modulus ratio E_L/E_T and thermal expansion ratio α_T/α_L, and 2) the boundary conditions and the orientation angles significantly affect the critical buckling temperature of laminated plates.
Evaluation of the environmental impact of the urban energy lifecycle based on lifecycle assessment

Energy resources have environmental impact through their entire lifecycle. The evaluation of the environmental impacts of the energy lifecycle can contribute to decision making regarding energy management. In this paper, the lifecycle assessment (LCA) method is introduced to calculate the environmental impact loads of different types of energy resources (including coal, oil, natural gas, and electricity) used in urban regions. The scope of LCA includes the production, transportation, and consumption processes. The pollutant emission inventory is listed, and the environmental impact loads are acquired through the calculation of environmental impact potentials, normalization, and weighted assessment. The evaluation method is applied to Beijing, China, revealing that photochemical oxidant formation and acidification are the primary impact factors in the lifecycle of all energy resources and that the total environmental impact load increased steadily from 132.69 million person equivalents (PE) in 1996 to 208.97 million PE in 2010. Among the energy types, coal contributes most to the environmental impact, while the impacts caused by oil, natural gas, and electricity have been growing. The evaluation of the environmental impact of the urban energy lifecycle is useful for regulating energy structures and reducing pollution, which could help achieve sustainable energetic and environmental development.
The impacts of climate change and human activities on grassland productivity in Qinghai Province, China

Qinghai Province, which is the source of three major rivers (i.e., Yangtze River, Yellow River and Lancang River) in East Asia, has experienced severe grassland degradation in past decades. The aim of this work was to analyze the impacts of climate change and human activities on grassland ecosystem at different spatial and temporal scales. For this purpose, the regression and residual analysis were used based on the data from remote sensing data and meteorological stations. The results show that the effect of climate change was much greater in the areas exhibiting vigorous vegetation growth. The grassland degradation was strongly correlated with the climate factors in the study area except Haixi Prefecture. Temporal and spatial heterogeneity in the quality of grassland were also detected, which was probably mainly because of the effects of human activities. In the 1980s, human activities and grassland vegetation growth were in equilibrium, which means the influence of human activities was in balance with that of climate change. However, in the 1990s, significant grassland degradation linked to human activities was observed, primarily in the Three-River Headwaters Region. Since the 21st century, this adverse trend continued in the Qinghai Lake area and near the northern provincial boundaries, opposite to what were observed in the eastern part of study. These results are consistent with the currently status of grassland degradation in Qinghai Province, which could serve as a basis for the local grassland management and restoration programs.
Transport of a volatile contaminant in a free-surface wetland flow

Presented in this paper is an analytical study of a pulsed volatile contaminant emission into a free-surface wetland flow. A simplified model is given for contaminant transport under the combined action of advection, mass dispersion, apparent reaction, and volatilization at the free water surface. The effect of periodic apparent reaction on contaminant transport is separated from the hydraulic effect via an extended transformation, with a limiting case covering the known transformation for constant apparent reaction rate. The analytical solutions of zeroth and first order concentration moments are rigorously derived and illustrated. It was found that the amount of contaminant decreases from the bottom bed to the free-surface under volatilization, and the total amount of contaminant decays with time. It was also found that the moving speed of the mass center of the whole contaminant cloud increases, as the ratio of volatilization coefficient to vertical effective mass dispersivity increases.
Positive eigenvalue-eigenvector of nonlinear positive mappings

We show that an (eventually) strongly increasing and positively homogeneous mapping T defined on a Banach space can be turned into an Edelstein contraction with respect to Hilbert’s projective metric. By applying the Edelstein contraction theorem, a nonlinear version of the famous Krein- Rutman theorem is presented, and a simple iteration process {T~kx/∥Tkx∥} (? x ∈ P~+) is given for finding a positive eigenvector with positive eigenvalue of T. In particular, the eigenvalue problem of a nonnegative tensor A can be viewed as the fixed point problem of the Edelstein contraction with respect to Hilbert’s projective metric. As a result, the nonlinear Perron-Frobenius property of a nonnegative tensor A is reached easily.
Construction of periodic wavelet frames with dilation matrix

An important tool for the construction of periodic wavelet frame with the help of extension principles was presented in the Fourier domain by Zhang and Saito [Appl. Comput. Harmon. Anal., 2008, 125: 68-186]. We extend their results to the dilation matrix cases in two aspects. We first show that the periodization of any wavelet frame constructed by the unitary extension principle formulated by Ron and Shen is still a periodic wavelet frame under weaker conditions than that given by Zhang and Saito, and then prove that the periodization of those generated by the mixed extension principle is also a periodic wavelet frame if the scaling functions have compact supports.
中国白杨派杨树叶片表皮特征的研究

运用光镜和扫描电镜对中国9种白杨派杨树叶片的表皮特征进行了研究, 结果表明该派植物的气孔器为不规则型, 仅分布于叶片的背面, 气孔器与表皮细胞平齐、不呈下陷状, 大小变化较大; 表皮毛为单细胞、非腺性的长绒毛, 毛细长而扁平, 不具分支, 气孔器密度、表皮毛、角质层和蜡质层等表皮特征不仅与树种有关, 而且在同一树种的长枝叶与短枝叶之间, 也有明显的差异。另外, 还对白杨派杨树的生态类型进行了探讨。
杏种子超低温伤害的研究

液氮保存杏种子伤害情况大体分为三类。整个子叶伤害后, 只要种胚具有活力, 仍能用组织培养方法获得新植株。子叶局部损伤, 延迟种子萌发3-4d, 萌发后12d左右的期 间内, 苗木生长稍慢。种胚伤害, 则不能成苗, 随着种子损伤程度的增加, 电解质渗出率也增加, 说明杏种子超低温导致了质膜伤害。
土麦冬离体萌发花粉管中生殖细胞与营养核的动态变化

多数花粉管中, 生殖细胞与营养核贴合后, 开始进行有丝分裂, 贴合时, 营养核略呈 弥散状态。在分裂早中期, 生殖细胞与营养核分开, 从贴合到分开大约经历3-5h, 精 子形成后, 不与营养核连接。DAPI对生殖细胞的有丝分裂有抑制作用。少数花粉管中,  生殖细胞核进行无丝分裂, 有缢裂和劈裂两种方式。生殖细胞核发生缢裂的花粉管中, 未观察到生殖细胞与营养核的贴合现象。劈裂仅发生于含DAPI培养基的花粉管内, 部分未萌发花粉中, 生殖细胞核发生内缢, 或营养核与生殖细胞从萌发沟处出, 呈各种形状。
黄土高原白羊草草原的基本特征及其地理学意义

黄土高原的白羊草草原具有水平地带性特性, 是第三纪亚洲内陆热带性质的草原随着 干旱的发展和气候的变冷逐渐向外推移的结果。因而该草原是次生的, 残遗的, 该区现在的分布区正是欧亚陆外围残遗的分布区的组成部分。该草原分布通常与森林相结合或形成群落复合体。草原西部和北部边缘应是中亚与东亚植物区系的自然界限, 即恒山-雁门关-管涔山-白于山-六盘山-天水-武山。草原的建群种和优势种主要为温带至亚热带分布, 既具有亚热带草原的性质, 也具有明显的温带草原旱生种类, 反应出其过渡的性质。
干旱对小麦幼苗诱导蛋白表达与某些生理特性的初步探讨

水分胁迫诱导小麦幼芽及整株均产生48.4kD、41.5kD二个蛋白质亚基。在幼根中,未出现以上二个蛋白亚基。胁迫48h后,根干重/芽干重比呈上升趋势,幼芽细胞膜相对透性增大和相对含水量下降幅度均大于幼根。复水48h,幼芽迅速恢复生长,表现出一个补偿性生长阶段,而主胚根部分死亡,随后,又重新从根鞘中发出新根。再胁迫时,幼根细胞膜相对透性增大和相对含水量下降幅度均大于幼芽,此时,根干重/芽干重比呈下降趋势,表明脱水能存活幼芽组织和诱导蛋白积累之间具有一定的相关性。
汞对玉米幼苗膜脂过氧化及体内保护系统的影响

随着处理HgCl_(2)浓度的升高,细胞膜脂质过氧化水平升高,细胞膜透性增大,CAT活性降低,SOD、POD活性升高,组织可溶性蛋白质含量升高。
披碱草属3个种的核型研究

首次报道了我国青藏高原3种披碱草属植物的核型,即短芒披碱草(E. brachyaristatus A.love),核型为2n=6x=42=32m+10sm(4SAT),属2A类型;无芒披碱草(E. submuticus (Keng) Keng f.),核型为2n=6x=42=30m+12sm(2SAT),属2A类型;硕穗披碱草(E. barystachyus L.B.Cai),核型为2n=6x=42=32m+10sm(4SAT),属2B类型。
小麦与珍珠粟远缘杂交的受精作用和胚胎发育

对波斯小麦、“中国春”小麦与珍珠粟远缘杂交的受精作用和胚胎发育进行了研究。 珍珠粟花粉管能在小麦柱头上萌发,并且有多个花粉管进入花柱及胚囊。波斯小麦已授粉的207个子房中,11.11%既形成胚又形成胚乳,7.25%只形成胚,而1.93%只形成胚乳,在这个杂交中受精率和成胚率分别为20.29%和18.36%。“中国春”小麦已授粉的167个子房中,相应的数字是2.99%、5.99%、0、8.98%和8.98%。杂交后形成的胚和胚乳核型极不稳定,来自珍珠粟的染色体很快被排除,最后产生的是单倍体的小麦胚。但因无胚乳或胚乳败育,幼胚缺乏营养供应而停止发育或夭亡。