mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
UV-B辐射对大型海藻鼠尾藻抗氧化酶活性及同工酶谱的影响

选择1种代表性的潮间带大型海藻鼠尾藻(Sargassum thunbergii)为试材,研究了其抗氧化酶体系对不同剂量UV-B胁迫的响应.结果显示,SOD及其CAT酶活性与UV-B辐射的剂量和时间关系密切,而POX活性与此相关不显著.各处理和对照中均未测出有效的APX活性.抗氧化剂AsA含量在低、中剂量UV-B辐射时呈增加趋势.SOD同工酶谱受到UV-B辐射的显著影响.中度剂量下CAT酶出现新的谱带(CATⅡ).低、中剂量胁迫下POXⅡ活性有轻微增加,而在此次研究中,未能检测到APX同工酶谱带.这些结果表明鼠尾藻中SOD与CAT酶活性及AsA水平对UV-B辐射增强响应最敏感,在该藻抗紫外胁迫的应激反应体系中处于核心地位.
放牧压力对草原砂质栗钙土土壤酶活性影响的研究

重点就不同放牧压力下土壤酶活性、进行了较为系统的研究.土壤酶活性在土壤生态系统的物质循环和能量运转过程中起着不可忽视的作用.研究结果表明:(1)土壤酶活性随着放牧压力的增大,呈现先增大然后减小的趋势,总的来看最小值出现在放牧压力为6.67只羊/hm~2或5.33只羊/hm~2处,并且大部分酶活性最大值出现在4.00只羊/hm~2,超出这个水平土壤酶活性就会减少;(2)除磷酸酶外放牧压力的处理之间过氧化氢酶、脲酶、转化酶差异并不显著,四种酶活性中只有脲酶活性在各放牧处理间酶活性高于未放牧处理土壤酶活性;(3)测试的四种酶中,绝大部分酶的活性与土壤有机质的含量相关性较大.放牧使草原土壤酶活性有所改变,并以磷酸酶活性的变化较为明显.另外,就放牧对草原土壤性质的影响来看和土壤酶活性的角度讲2.67只羊/hm~2应该是草原砂质栗钙土的最适放牧率,而4.00只羊/hm~2则是安全放牧的上限.
Screening-Dependent Study of Superconductivity in 3d-Transition Metals Binary Alloys Superconductors

In the present article, we report the screening-dependent study of the superconducting state parameters (SSPs), viz. electron-phonon coupling strength A, Coulomb pseudopotential μ~*, transition temperature Tc, isotope effect exponent a, and effective interaction strength N_oV of 3d-band transition metals binary alloys superconductors have been made extensively in the present work using a model potential formalism and employing the pseudo-alloy-atom (PAA) model for the first time. Five local field correction functions proposed by Hartree (H), Taylor (T), Ichimaxu-Utsumi (IU), Farid et al. (F) and Sarkar et al. (S) are used in the present investigation to study the screening influence on the aforesaid properties. The present results of the SSPs obtained from H-screening are found in qualitative agreement with the available experimental data wherever exist.
Transport Properties of Si and Ge Liquid Semiconductor Metals

In the present article, we study the electrical resistivity p, the thermoelectric power (TEP) α, thermal conductivity σ, Knight-ShiFts and temperature coefficient of the Knight-Shifts of the liquid Si and Ge using the well known model potential for the first time. The structure factor used in the present work is derived From the Percus-Yevick (PY) theory. Various local field correction Functions are used to study the screening influence. The present results of resistivity are found in qualitative agreement with available experimental and theoretical whenever exists.
Quantum to Classical Transition in a System of Two Coupled Kicked Rotors

We investigate the quantum-classical transition in a system of two coupled kicked rotors. We find that when the mass of one kicked rotor is much smaller than the other's, the influence of the light kicked rotor is still able to make decoherence of the heavy one. This leads to the quantum-classical transition of the heavy kicked rotor. We demonstrate this by two different coupling potentials.
9例心源性猝死相关因素临床分析

2008年AHA、ACC、ESC共同修订了心源性猝死(Sudden cardiac death, SCD)的定义[1],即发生在医院外、急诊室或送往医院的途中,任何心脏疾病导致的,症状发作1 h内的死亡.死亡原因可能是心室颤动,室性心动过速,心室停搏或非心律失常原因.猝死的预防和救治,是各层医疗单位面临的重要课题,中老年人是SCD的易发群体.本文对上海某军队离职干部休养所210例离休老干部中9例猝死患者相关危险因素进行了分析.
舒芬太尼复合雷米芬太尼对支撑喉镜手术患者术中血流动力学及术后苏醒的影响

在支撵喉镜下行声带手术,喉镜机械刺激可引起患者术中强烈的应激反应,甚至可导致心血管系统不良反应,而加深麻醉往往又会延长苏醒时间.本研究比较舒芬太尼复合雷米芬太尼以及单纯使用舒芬太尼或雷米芬太尼三种麻醉方案在支撑喉镜下行声带手术对患者血流动力学、心血管应激反应的影响和苏醒时间及质量,以寻找一种能有效控制或减轻喉镜置入时及术中心血管应激反应,且术毕能尽快苏醒,同时又减轻患者苏醒时的躁动反应的最佳麻醉方案.
Adaptive Execution of Jobs in Computational Grid Environment

In a computational grid,jobs must adapt to the dynamically changing heterogeneous environment with an objective of maintaining the quality of service.In order to enable adaptive execution of multiple jobs running concurrently in a computational grid,we propose all integrated performance-based resource management framework that is supported by a multi-agent system(MAS).The multi-agent system initially allocates the jobs onto different resource providers based on a resource selection algorithm.Later,during runtime,if performance of any job degrades or quality of service cannot be maintained for some reason(resource failure or overloading),the multi-agent system assists the job to adapt to the system. This paper focuses on a part of our framework in which adaptive execution facility is supported.Adaptive execution facility is avmled by reallocation and local tuning of jobs.Mobile,as well as static agents are employed for this purpose.The paper provides a summary of the design and implementation and demonstrates the efficiency of the framework by conducting experiments on a local grid test bed.
高速经编机电子横移系统运动精度分析

针对电子横移系统不能适应高速经编机的发展要求,影响高速经编机全面电子化控制的问题,通过对电子横移系统的工作原理与工艺要求的研究,从系统控制和机械结构2方面分析影响横移运行精度的因素.结果表明:在系统控制方面,控制方式、驱动运动规律、电子齿轮比设置、跟随误差、反馈方式与精度、主轴信号装置是影响横移运动精度的因素;在机械结构方面,直线伺服电机的选型与安装、顶杆长度、电机运动轴与梳栉的平行度是横移运动精度的主要影响因素.
磷酸盐-硅系纳米浆料助剂的分散稳定性

为研究纳米浆料助剂的稳定性对淀粉浆料性能的影响,分别以Na3PO4,Na4P2O7,(NaPO3)6和Na5P3O10为分散剂制备纳米SiO2浆料助剂,通过离心透光率、沉降积等指标表征该磷酸盐-硅系纳米浆料助剂的分散稳定性,研究其分散稳定性对淀粉浆液、浆膜及黏附性能的影响.实验表明:Na3PO4,Na4P2O7,(NAPO3)6和Na5P3O10的分散稳定能力依次增强,质量分数分别为0.5%,4%,8%和10%时分散效果最佳;这种助剂对淀粉浆液性能没有显著影响,对浆膜断裂强度及黏附性能的促进作用随着分散体系稳定性的提高而增强;以Na5P3O10为分散剂的纳米浆料助剂对淀粉浆料性能的促进作用最显著.
地铁运行引起的地面振动实测及传播规律分析

对地铁线路某区间段的地面振动进行实测,采集不同测线和不同测点处的水平方向、竖直方向加速度,并转化为傅里叶幅值谱对其进行衰减规律分析.利用公式将加速度记录换算为振级和分频振级,参照相关的国家标准分析不同距离处的振级和频率成分.对比同一加速度记录中的两对开方向列车引起的地面振动,进一步分析振动衰减的规律.所得到的结果可供地面建筑的隔振减振及城市轨道的规划和设计参考.
强震地面运动的混沌特性分析

引入非线性动力学理论和混沌时间序列分析方法考察强震地面运动加速度时程的非线性特征.首先采用功率谱分析法、主成份分析法和Cao方法定性判断地震动加速度时程具有混沌特性,然后应用混沌时间序列分析方法定量计算了30条地震动加速度时程的三个非线性特征参数.计算表明,这些地震动时程的关联维数为2.O～4.0的分数维,Kolmogorov熵Kz为大于零的有限正值,最大Lyapunov指数在O～1.0之间.结果说明,强震地面运动具有混沌特性,地震动的高度不规则和复杂性是地震过程强非线性的反映.
芳香化酶抑制剂在卵巢低反应者超促排卵中的作用

目的 研究芳香化酶抑制剂来曲唑对卵巢低反应者超促排卵效果的影响,并探讨其作用机制.方法 至少接受过1次超促排卵治疗,卵巢反应低下者45例,分为研究组24例,周期第1~3天口服来曲唑 2.5 mg,1次/d,周期第4天开始应用醋酸曲普瑞林及基因重组促卵泡激素超促排卵,按体外受精程序进行治疗;对照组21例不使用来曲唑,周期第4天开始治疗同研究组.两组均于第4天、注射绒毛膜促性腺激素(hCG)日抽取静脉血,检测促卵泡激素(FSH)、促黄体生成激素、雌二醇、总睾酮、抗苗勒氏管激素(AMH)、抑制素B,收集卵泡液,检测雌二醇、总睾酮、AMH、抑制素B,比较两组FSH使用总剂量、hCG日内膜厚度、获卵数、受精率、可移植胚胎数、胚胎种植率、临床妊娠率.结果 与对照组比较,研究组注射FSH总剂量减少,但差异无统计学意义(P>0.05),hCG日内膜厚度无明显降低,受精率、胚胎种植率、临床妊娠率无显著差异,但获卵数、可移植胚胎数显著增加(P<0.05).研究组第4天血清雌二醇水平显著降低(P<0.05),总睾酮、AMH、抑制素 B水平显著升高(P<0.05),血清FSH、促黄体生成激素无显著差异.hCG日血清总睾酮升高(P<0.05),其余指标均无显著差异.研究组取卵日卵泡液总睾酮、抑制素B水平较对照组显著升高(P<0.05),雌二醇及AMH水平无显著差异.结论 对于卵巢低反应者,超促排卵前短期低剂量应用芳香化酶抑制剂,通过提高血清或卵泡液内雄激素、AMH、抑制素B水平募集更多卵泡,可以使获卵数和可移植胚胎数增多,不改变内膜厚度和形态,对提高妊娠率起到有利作用.
左股中间肌包虫并感染1例分析

1 临床资料 患者,男性,38岁,汉族,专职司机.于入院前10 d 下蹲站立时自觉左大腿内侧疼痛,扪及左大腿上段内侧有1肿物,压痛明显,休息后无缓解.入院查体:左人腿中上段肿大,周径较右大腿粗2 cm,无发红、破溃、表面静脉无怒张,中上段前内侧可触及直径约8 cm肿物、边界清,活动度良好,压痛阳性.
硝呋太尔制霉素阴道软胶囊治疗外阴阴道假丝酵母菌病64例临床疗效

0 引言 外阴阴道假丝酵母菌病(vuLvovagihal candidiasis,VVC)是由假丝酵母菌引起的常见的外阴阴道炎症.资料显示,约75%妇女一生中至少患过1次外阴阴道假丝酵母菌病,45%妇女经历过2次或2次以上的发作[1].
基于探地雷达信号处理的小波基选取研究

针对探地雷达信号处理和分析时小波基选取存在的问题,本文在分析探地雷达信号特点的基础上,首先从理论上讨论小波基的选取准则,然后再从实验角度进行对比、判别,认为在进行小波分解和重构时应该分别选择不同的小波基函数进行处理,这样可以保证重构信号的精确度,增强对信号的处理能力,从而也突破了以往分解与重构时都采用同一个小波基进行处理的做法.最后通过实际资料的处理,指出bior2.6小波基在进行雷达信号处理时效果最佳,不仅去噪彻底,而且能够保留有效信号的高频部分,提高信号的分辨率和信噪比,为后续解释工作打好了基础.
InSAR技术用于西安地区1992～1993年间活动地裂缝的定位研究

西安地裂缝是一种典型的地质灾害,自首次出现至今已有近半个世纪.基于活动地裂缝造成的形变去相干特征,通过分析滤波后的差分干涉图的伪相干图来提取活动地裂缝的位置信息.采用两幅ERS影像对西安地区1992～1993年间的活动地裂缝进行了定位研究,通过与该时间段工程地质调查的地裂缝位置比较发现二者有很强的一致性.通过该时间段地裂缝水准对点监测资料比较发现活动地裂缝区域易于产生相位解缠粗差,因此在后续采用差分InSAR获取地裂缝不连续形变信息时需要特别注意.
双相介质的AVO资料中蕴含的流体信息的定量分析

振幅随偏移距变化(AV0)弹性参数的反演是储层预测的一个重要方法.利用正演技术分析双相介质的地震资料中含有的流体信息,有助于提高AVO弹性参数反演的可靠性.本文应用Russell推出的计算纵波反射系数的AVO线性近似公式,对双相介质的纵波资料中所含有的流体信息进行定量分析,研究从AV0资料的反演中可以确定哪些弹性参数或它们的组合关系.文中考虑的弹性参数有流体因子、剪切模量和密度三者的相对扰动量.在时间城内对反射系数的正演计算公式进行线性化,得到灵敏度矩阵,并用奇异值分解(SVD)计算其特征值和特征向量采分析弹性参数的反演.由计算结果可知,在入射角较小时由AV0资料反演只能得到流体因子和密度两者的相对扰动量;若想同时获得三个参数的相对扰动量,就必须增大入射角.
Parameterizations of the Daytime Friction Velocity, Temperature Scale, and Upslope Flow over Gently Inclined Terrain in Calm Synoptic Conditions

A set of new parameterizations for the friction velocity and temperature scale over gently sloped terrain and in calm synoptic conditions are theoretically derived. The friction velocity is found to be proportional to the product of the square root of the total accumulated heating in the boundary layer and the sinusoidal function of the slope angle, while the temperature scale is proportional to the product of the boundary layer depth, the sinusoidal function of the slope angle and the potential temperature gradient in the free atmosphere. Using the new friction velocity parameterization, together with a parameterization of eddy diffusivity and an initial potential temperature profile around sunrise, an improved parameterization for the thermally induced upslope flow profile is derived by solving the Prandtl equations. The upslope flow profile is found to be simply proportional to the friction velocity.
Tropical Cyclones and Polar Lows: Velocity, Size,and Energy Scales, and Relation to the 26°C Cyclone Origin Criteria

The goal of this paper is to quantitatively formulate some necessary conditions for the development of intense atmospheric vortices. Specifically, these criteria are discussed for tropical cyclones (TC) and polar lows (PL) by using bulk formulas for fluxes of momentum, sensible heating, and latent heating between the ocean and the atmosphere. The velocity scale is used in two forms: (1) as expressed through the buoyancy flux b and the Coriolis parameter l_c for rotating fluids convection, and (2) as expressed with the cube of velocity times the drag coefficient through the formula for total kinetic energy dissipation in the atmospheric boundary layer. In the quasistationary case the dissipation equals the generation of the energy. In both cases the velocity scale can be expressed through temperature and humidity differences between the ocean and the atmosphere in terms of the reduced gravity, and both forms produce quite comparable velocity scales. Using parameters b and l_c., we can form scales of the area and, by adding the mass of a unit air column, a scale of the total kinetic energy as well. These scales nicely explain the much smaller size of a PL, as compared to a TC, and the total kinetic energy of a TC is of the order 10~(18) - 10~(19) J. It will be shown that wind of 33 m s~(-1) is produced when the total enthalpy fluxes between the ocean and the atmosphere are about 700 W m~(-2) for a TC and 1700 W m~(-2) for a PL, in association with the much larger role of the latent heat in the first case and the stricter geostrophic constraints and larger static stability in the second case. This replaces the mystical role of 26℃ as a criterion for TC origin. The buoyancy flux, a product of the reduced gravity and the wind speed, together with the atmospheric static stability, determines the rate of the penetrating convection. It is known from the observations that the formation time for a PL reaching an altitude of 5-6 km can be only a few hours, and a day, or even half a day, for a TC reaching 15-18 km. These two facts allow us to construct curves on the plane of T_s and △T= T_s - T_a to determine possibilities for forming an intense vortex. Here, T_a is the atmospheric temperature at the height z = 10 m. A PL should have △T > 20℃ in accordance with the observations and numerical simulations. The conditions for a TC are not so straightforward but our diagram shows that the temperature difference of a few degrees, or possibly even a fraction of a degree, might be sufficient for TC development for a range of static stabilities and development times.
Variations in Extratropical Cyclone Activity in Northern East Asia

Based on an improved objective cyclone detection and tracking algorithm, decadal variations in extratropical cyclones in northern East Asia are studied by using the ECMWF 40 Year Reanalysis (ERA-40) sea-level pressure data during 1958-2001. The results reveal that extratropical cyclone activity has displayed clear seasonal, interannual, and decadal variability in northern East Asia. Spring is the season when cyclones occur most frequently. The spatial distribution of extratropical cyclones shows that cyclones occur mainly within the 40°-50°N latitudinal band in northern East Asia, and the most frequent region of occurrence is in Mongolia. Furthermore, this study also reveals the fact that the frequency of extratropical cyclones has significantly decreased in the lower latitude region of northern East Asia during 1958-2001, but dccadal variability has dominated in higher latitude bands, with frequent cyclone genesis. The intensity of extratropical cyclones has decreased on an annual and seasonal basis. Variation of the annual number of cyclones in northern East Asia is associated with the mean intensity of the baroclinic frontal zone, which is influenced by climate warming in the higher latitudes. Moreover, the dipole structure of extratopical cyclone change, with increases in the north and decreases in the southern part of northern East Asia, is related to the northward movement of the baroclinic frontal zone on either side of 110°E.
Winter Season Stratospheric Circulation in the SAMIL/LASG General Circulation Model

In this paper, we examine the performance of the 26-level version of the SAMIL/LASG GCM (R42/L26)in simulating the seasonal cycle and perpetual winter mean stratospheric circulation as well as its variability by comparing them with the NCEP/NCAR reanalysis. The results show that the model is capable of reproducing many key features of the climatology and seasonal variation of the stratospheric circulation despite that the model's mean polar vortex is stronger and more zonally symmetric compared to the observation. Further diagnosis of the results from a perpetual-January-run of the SAMIL/LASG GCM indicates that the dominant winter-season oscillation mode in the model's stratosphere exhibits a similar inter-seasonal timescale with similar spatial patterns as those inferred from the NCEP/NCAR reanalysis. In particular, the simulated polar vortex oscillation mode exhibits a dominant inter-seasonal timescale of about 120 days, and is accompanied with the simultaneous poleward and downward propagation of temperature anomalies in the stratosphere and the equatorward propagation of temperature anomalies in the troposphere. More encouragingly, the 26-layer version of the SAMIL/LASG GCM is able to produce three strong Stratospheric Sudden Warming events during the 1825 days of perpetual-January integration, with the polar westerly jet completely reversed for a few weeks without imposing any prescribed anomalous forcing at the lower boundary.
A Comparison Study of the Methods of Conditional Nonlinear Optimal Perturbations and Singular Vectors in Ensemble Prediction

The authors apply the technique of conditional nonlinear optimal perturbations (CNOPs) as a means of providing initial perturbations for ensemble forecasting by using a barotropic quasi-gcostrophic (QG) model in a perfect-model scenario. Ensemble forecasts for the medium range (14 days) are made from the initial states perturbed by CNOPs and singular vectors (SVs). 13 different cases have been chosen when analysis error is a kind of fast growing error. Our experiments show that the introduction of CNOP provides better forecast skill than the SV method. Moreover, the spread-skill relationship reveals that the ensemble samples in which the first SV is replaced by CNOP appear supcrior to those obtained by SVs from day 6 to day 14. Rank diagrams are adopted to compare the new method with the SV approach. The results illustrate that the introduction of CNOP has higher reliability for medium-range ensemble forecasts.
Ensemble-based Kalman Filters in Strongly Nonlinear Dynamics

This study examines the effectiveness of ensemble Kalman filters in data assimilation with the strongly nonlinear dynamics of the Lorenz-63 model, and in particular their use in predicting the regime transition that occurs when the model jumps from one basin of attraction to the other. Four configurations of the ensemble-based Kalman filtering data assimilation techniques, including the ensemble Kalman filter, ensemble adjustment Kalman filter, ensemble square root filter and ensemble transform Kalman filter, are evaluated with their ability in predicting the regime transition (also called phase transition) and also are compared in terms of their sensitivity to both observational and sampling errors. The sensitivity of each ensemble-based filter to the size of the ensemble is also examined.
Summertime Atmospheric Teleconnection Pattern Associated with a Warming over the Eastern Tibetan Plateau

By using a surface air temperature index (SATI) averaged over the eastern Tibetan Plateau (TP), investigation is conducted on the short-term climate variation associated with the intcrannual air warming (or cooling) over the TP in each summer month. Evidence suggests that the SATI is associated with a consistent teleconnection pattern extending from the TP to central-western Asia and southeastern Europe. Associated rainfall changes include, for a warming case, a drought in northern India in May and June, and a stronger mei-yu front in June. The latter is due to an intensified upper-level northeasterly in eastern China and a wetter and warnmr condition over the eastern TP. In the East Asian regions, the time-space distributions of the correlation patterns between SATI and rainfall are more complex and exhibit large differences from month to month. Some studies have revealed a close relationship between the anomalousheating over thc TP and the rainfall anomaly along the Yangtze River valley appearing in the summer on a seasonal mean time-scale, whereas in the present study, this relationship only appears in June and the signal's significance becomes weaker after the long-tcrm trend in the data was excluded. Close correlations between SATI and the convection activity and SST also occur in the western Pacific in July and August: A zonally-elongated warm tone in the SST in the northwestern Pacific seems to be a passive response of the associated circulation related to a warm SATI. The SATI-associated teleconnection pattern provides a scenario consistently linking the broad summer rainfall anomalies in Europe, central-western Asia, India, and East Asia.
中扬子北缘上侏罗统-白垩系沉积岩地球化学特征与构造背景分析

沉积岩中的微量元素和稀土元素特征对沉积环境、沉积物的物源和构造背景具有十分重要的示踪与指示作用.对采自中扬子北缘晚侏罗世-白垩纪地层的泥质岩样品中微量元素和稀土元素进行了测试与分析,结果表明,研究区微量元素中的深源元素普遍低于地壳粘土岩中的平均值,说明沉积物的来源为陆源物质,而典型陆源元素Zr、Hf的平均含量远高于地壳粘土岩中的平均含量,反映了大量的陆源物质的快速堆积.上侏罗统与下白垩孚统泥质岩的微量元素特征相似,而上白垩统则发生了明显的变化,表现为深源性微量元素含量较上白垩统明显降低,而陆源性微量元素含量显著增加,反映早晚白垩世之间沉积背景发生了变化.纵向上,稀土元素的变化规律显示,上白垩统与下白垩统的稀土元素特征具明显的差异,表现为Eu的负异常明显减小,Ce的负异常增大,轻稀土富集程度降低,反映了沉积作用分异度较低的特点.La-Th-Sc、Th-Co-Zr/10和Th-Sc-Zr/10构造环境判别图及La/Th-Hf和Th/Sc-Sc比值图表明,中扬子北缘晚侏罗世-白垩纪沉积岩物源区的构造背景以大陆岛弧型为主,可能也存在类似被动大陆边缘构造背景.
四川黄龙沟源头黄龙泉泉水及其下游溪水的水化学变化研究

用水化学仪器自动记录、现场滴定及取样室内分析等方法,对四川黄龙沟钙华景区水的物理化学动态变化特征进行了研究.结果发现,黄龙钙华的沉积主要起因于水中CO2的大量释放,造成溪流自黄龙泉泉口向下游方向水的二氧化碳分压(p(CO2))和电导率(EC)降低,pH值和方解石饱和指数(SIc)升高.但仔细分析发现,水化学的这一空间变化主要发生在SIc＜1.0时;当SIc＞1.0后,向下游方向,水化学趋于稳定.同时,黄龙沟地表融雪水和沿途泉水分别产生的稀释和浓集作用对溪流水化学的这一空间变化产生了明显的影响.此外,源头黄龙泉的水化学稳定,没有明显的日变化,而下游的池水则出现pH值、EC和SIc及p(CO2)的显著日变化,即白天p(CO2)、EC较低,而pH和SIc较高,反映了白天较快的碳酸钙沉积,其中温度和水生生物光合作用的影响可分别达到19%和81%.
念青唐古拉山东南坡高寒草原生态系统表层土壤有机碳分布特征及影响因素

对念青唐古拉山东南坡高寒草原生态系统表层(0～20 cm)土壤有机碳分布特征进行研究,结果表明:有机碳密度平均为5.002 8±1.103 7 kg/m3,变异系数21.96%;在拔4 421～4 598 m内,随海拔升高表现增加→减少→增加的分布特征;与地上及10～20 cm土层生物量、20～30 cm含水量、土壤有机质、速效N、全N和全P含量呈显著正相关,与20～40 cm容重呈显著负相关.影响其的第1因子是植被盖度、地上生物量、20～30 cm地下生物量和20～30 cm含水量,第2因子是0～20 cm和20～40 cm容重及全P量,第3因子是有机质含量和速效N含量,第4因子是0～10 cm地下生物量,累计贡献率92.83%.
1961～2000年中国生态区紫外辐射的时空演变特征

通过ANLJSPIINE空间插值以及气候学意义上的幂函数换算,探讨中围大陆生态区紫外辐射时空动态变化规律.结论如下:(1)紫外辐射多年平均值和多年季节平均值大致以季风区和非季风区分界为界线,呈现西部高东部低的总体格局,这主要与中国的地势和气候特点有关.(2)部分生态区40 a来年和四季紫外辐射呈显著减少趋势;冬季的紫外辐射年际间变化程度较大,其次是夏季和秋季,春季和年均紫外辐射年际变化较小;可分1961～1972、1973～1990、1991～2000年3个时段,大部分生态区第二时段年和季节紫外辐射平均值较小,第三时段普遍又开始增大,比第一时段小.
地理学的十四大原理

已有的地理学原理可以概括成十四大要义.其中的"区位选择与放弃、区位选择是一种空间优化"这两条是关于区位选择的基本要义.关于地球表面差异性的要点包括:"差异性的度量和解释受到尺度和规模的影响;热力差异是地表差异的基础;外驱动力对地理环境的形成与演变具有重要影响;风化、侵蚀、搬运和堆积是形成地表特性的一种基本自然过程;两地间的相互作用随其距离的增加而减小;地方的创造和发展建构了地球表层上差异化的关于人的世界;人口迁移、产品贸易与地表上的差异性互为因果."关于人地关系的原理包括:"人的个体或群体对空间上利益的竞争是人地关系的第一要义;地球表面的绝大多数要素的相互作用不能为人的个体或群体在其占据的空间内所掌控"."空间临界点"是地理分析的基本方法性原理."地球表面不同尺度上人类活动的外部性是分析环境问题产生的起点;个人之间观念的差异,地区之间、国家之间利益的差异是人们在对地球资源、环境的利用与保护方面发生分歧或对立的基本因素"是关涉地球表面开发保护政策的要义.
居住郊区化背景下消费空间的特征及其演化——以广州市为例

以广州市居住郊区化过程中出现的消费错位现象为切入点,从消费社会学的符号消费视角对其原因进行新的解释.消费空间剧场化、消费空间时尚化以及消费空间对消费者社会身份的建构功能,使北京路传统商业步行街作为高级商业中心地的符号功能得以建构.现代购物中心的符号表征功能,使天河区商业中心成为一个消费者自我实现的情感化消费空间.两者重构了大城市的中心-边缘关系,使到郊区的居住空间得以拓展而消费空间受到抑制,难以发展高等级的现代业态.随着城市快速轨道交通的建设,城区商业中心进一步加强了对消费者和经营者的吸引力,新时期的地下商业文化也加速了商业中心的符号化.城市消费空间正向城区商业中心极化力量增强的方向演化.
基于分形的中国地均农畜产品虚拟水规模分布的时空演变研究

虚拟水是当今水科学的研究热点,被认为是解决粮食与水资源安全的重要策略.在测算中国各地区农畜产品虚拟水总量的基础上,计算出1996～2006年中国农畜产品虚拟水与耕地资源的基尼系数,表明二者地区差异不大且在逐年减小.运用位序-规模法则,探讨差异背后的分形特征.研究表明:中国地均农畜产品虚拟水体系不具有首位分布的特征;双对数回归方程拟合度较高,符合位序-规模分布;分维值D大于1,且逐年升高,地均农畜产品虚拟水规模分布整体差距在缩小,均衡程度在增强;规模分布呈双分形结构,体现出地均农畜产品虚拟水大规模省市发展较慢且辐射带动作用较弱,中小规模的省市比较发育且发展较快.本文旨在揭示地均农畜产品虚拟水的空间分异特征规律,为制定不同区域类型的农业发展决策提供相应的理论参考.
旅游发展与乡村劳动力回流研究——以西递村为例

采取社会资本的研究视角,以安徽省南部世界文化遗产地西递村旅游发展与社会经济变迁的基本事实为案例,主要提出了一种对乡村外出劳动力向原社区回流并参与非农产业生产现象的社会经济解释.研究发现:①社区按年向有本社区户口的普通社区成员提供总收入相当比例的稳定收入,是吸引外出劳动力回流的重要原因;②社会资本和社会关系网络的效力在社区的空间范围之内才能得到发挥,是社区精英人物及与其有亲密关系的社区成员留守或回流的原因.
非差相位数据预处理的TurboEdit算法及其改进

对TurboEdit算法的3个关键环节进行改进:宽巷模糊度和方差考虑不同弧段、弧段长度、粗差影响等因素;两类组合观测值均通过探测连续3个历元的状态来决定当前历元是否为周跳或粗差;设计了一个基于滑动窗口的拟合模型,该模型更符合无周跳的Geometry-Free(G-F)组合观测值的平滑时间序列特征,同时对划分的G-F弧段可进行二次处理,进一步剔除小粗差.实验表明,该算法可探测并精确修复等周、等距和连续周跳,对连续粗差和表现并不明显的粗差,亦能有效剔除.
人工地震信号检测中相位信息的利用

针对固定台接收到的小药量激发的人工震源信号信噪比低的问题,基于人工震源激发的相似性,采用相位互相关和相位权重叠加的方法检测固定台站接收到的微弱信号,提高了弱信号的检测能力,可在200 km距离处接收到数十千克当量的炸药激发的信号.
影响武汉台重力和垂直位移观测的环境因素

利用武汉台超导重力仪和同址的GPS连续观测数据,研究重力变化和垂直位移与主要环境因素之间的关系.采用经典的弹性地球表面负荷理论,模拟计算大气、非潮汐海平面变化(海底压力)和陆地水等环境负荷对重力和垂直位移的贡献.结果表明,3种环境因素对重力和垂直位移的周年振幅贡献分别为90%和75%.目前采用的全球陆地水同化模型LaD及GLDAS,不能客观地反映台站局部水储量的实时变化,由此得到的理论模拟结果与实际观测结果之间存在明显的时间延迟.
泾阳台短水准异常与地震关系研究

汶川8.0级地震发生前3个月,陕西省泾阳地震台短水准出现向南的下滑异常,异常最大幅度2.2 mm.2001年2月23日四川雅江6.0级、1995年10月24日云南武定6.5级和1995年12月18日青海玛多6.2级地震期间也出现了同类异常现象.用反演方法求得地震震级与震中距、异常幅度等的关系式为M=0.002 8L+1.126 9H+0.076 8T.
中国大陆近期重力场动态变化图像

根据1998年以来中国大陆地壳运动网络、中国数字地震观测网络重力网流动观测成果,给出中国大陆1998年以来2-3年尺度的中国大陆动态重力场变化图像,并结合中国动力构造环境和强震活动进行了分析.分析表明,中国大陆动态重力场变化图像基本反映了中国大陆近期地壳物质运动和主要强震活动的基本轮廓.
全球大震和中国及邻区中强震地震活动(2009年7-8月)

本目录中的地震参数来自"中国地震台站观测报告"(简称"月报").其中,国内及邻区给出M≥4.7的事件,全球给出M≥6的事件."月报"由中国地震台网中心按月做出.
变量播种施肥技术研究

由于种子的播种量不精确,化肥的施用存在利用率低、污染环境等问题.为了解决这些问题,必须进行精准变量播种施肥,变量播种施肥技术是精准农业的重要内容之一.文章介绍了精准农业的基本概念,并以精准农业为背景,介绍了变量播种施肥的概念及关键技术,探讨了当前变量播种施肥技术存在的问题及未来的发展前景.
黑加仑物理力学特性研究

通过黑加仑基本物理力学特性的测试与分析,得到了布劳德杂交X14-1和东农大粒两个品种黑加仑果粒直径的分布范围分别为(11.1±3.18)、(11.7±3.54)mm,质量的分布范围分别为(0.87±0.72)、(1.0±0.9)g,密度的分布范围分别为(1.16±0.14)、(1.13±0.12)g·cm-3;黑加仑果实与果柄结合部位的抗拉强度、浆果名义抗压极限和刚度等力学特性指标随成熟度和采收日期的变化规律.为黑加仑采收机械系统的研制提供了设计依据.
小麦抗条锈病基因分子标记及定位研究进展

条锈病是小麦的主要病害之一,在我国曾多次流行造成小麦严重减产.近年来分子标记技术的迅速发展为小麦抗条锈病基因的研究提供了极大的方便.在抗痛育种中应用分子标记辅助选择有利于实现抗条锈病多基因积累,可以加速持久抗病品种的培育进程.本文简要介绍了几种常用的分子标记的概念和方法,并详细介绍了近几年分子标记在小麦抗条锈基因定位的应用现状,展望了DNA分子标记技术在小麦抗条锈病研究中的前景.
沙棘提取物对断奶仔猪消化机能的影响

选取28日龄长×大二元断奶仔猪24头,随机分两处理组,每个处理3个重复,每个重复4头,对照组饲喂基础日粮,试验组饲喂添加0.1%沙棘提取物的日粮,试验期28 d.试验结束时测定胃、胰腺和小肠内容物的胃蛋白酶;胰腺和十二指肠的淀粉酶、脂肪酶、蛋白酶;胃黏膜厚度、小肠各段绒毛高度和隐窝深度.结果表明,在饲料中添加0.1%沙棘提取物可显著提高断奶仔猪消化酶活性以及空肠和回肠的绒毛高度(P<0.05),并可改善断奶仔猪消化机能,缓解仔猪的断奶应激.
CO2浓度与温度增高对水稻品质的影响

作物品质的形成是品种遗传特性和环境条件综合作用的结果.大气中CO2:浓度增高必然影响作物的生理代谢,并因此可能影响作物品质;CO2浓度增高也会引起大气温度同步增高.本试验旨在明确不同CO2浓度和温度水平对水稻品质的影响程度,结果显示,随CO2浓度和温度增高,稻米的加工品质和外观品质各指标均有下降趋势;蒸煮品质指标先上升,在CO2浓度为500 mg·kg-1时达到最大值,然后下降;营养品质指标变化比较复杂,糖含量上升,脂肪含量下降.蛋白质含量先上升后下降,在CO2浓度为500 mg·kg-1时达到最大值.总体上,CO2浓度和温度增高对稻米品质的负面影响更大,特别表现在加工品质和外观品质方面.但在450～650 mg·kg-1的处理区间,影响结果并没有达到显著水平.表明CO2浓度和温度增高改变了水稻C、N代谢过程和籽粒的物理成分与化学组分;依据CO2与温度对稻米品质影响机理,采取相应的适应措施,可以提高和改进稻米品质.
SBR乳液对水泥砂浆长期收缩性能影响及机理分析

采用螺旋弓形测量仪分别测量了普通水泥砂浆和SBR(styrene-butadiene rubber)乳液改性水泥砂浆长期(1～90 d)收缩变形,并通过孔径分布法、密度法和SEM图像法对28 d砂浆的微观形貌及孔结构特征进行了分析,并对SBR乳液水泥净浆的水化热进行了测试.结果表明,乳液掺量超过水泥质量的3%后能有效改善砂浆长期收缩性能,特别是改善砂浆28 d龄期前的收缩性能,且乳液掺量越大,砂浆收缩长期变形越小.SBR乳液对砂浆收缩性能改善机理主要有以下几点:1)SBR乳液的掺入减小了砂浆早期(72 h前)水化热,起到减少收缩开裂的效果;2)在水泥水化过程中,乳液水分的丧失,形成了聚合物薄膜,起到了"微纤维"作用,限制了收缩;3)SBR乳液的掺入使砂浆的平均孔径、最可几孔径及中值孔径等特征孔径减小、有害孔及多害孔数量减少,而无害孔增多.表明乳液的掺入起到了改善砂浆微观结构的作用效果;4)使砂浆的总孔隙率略有下降,闭口孔隙率在总孔隙中所占比重大幅度增加,起到了保持砂浆内部水分的作用.
山地城市河流健康内涵及评价

山地城市河流健康评价是实现山地城市河流可持续控制的重要工具.对河流健康内涵及山地城市河流特点进行了概要分析,认为山地城市河流健康应以山地河流生态系统为基本单元,并具有4个方面的内涵:河流内部的生态完整性、弹性和恢复力、河流与城市空间景观格局的安全性、河流与城市人群关系的和谐性,以及河流上述关系在时间上的可持续性.在此基础上提出了山地城市河流健康评价的指标体系,作为山地城市河流健康评价的重要工具,并认为评价时应利用地理信息系统工具加强空间景观格局的分析.
渗透变形中相似性问题的颗粒流模拟

在离心试验中进行渗流试验一般采用原型土,由于土样没有和模型同比缩放,导致试验中流体流动不遵循流体动力学相似准则.在分析离心试验结果的基础上,对照流体动力学相似准则,提出通过调整颗粒粒径和流体材料参数,获得模型和原型的完全相似.由于颗粒粒径和流体材料参数调整具有一定的难度,根据离散单元法的特点,考虑采用颗粒流程序对离心试验中的渗透变形问题进行模拟.数值模拟结果表明模型和原型中的流场可以实现较好的相似,与理论及试验结果一致.说明采用颗粒流程序进行离心试验是可行的,同时为颗粒流在涉及渗流过程的离心试验中进一步运用提供了参考.