关于δ-Pinching流形中具有平行第二基本形式的子流形

研究了δ-Pinching流形中具有平行第二基本形式的子流形,获得了这类子流形的第二基本形式模长平方的一个拼挤定理。     

Illustrations with Real Examples of Using Ecological Regulation Strategies Against Crop Pests in China

In this paper, a series of examples from China, including those using ecological regulation strategies successfully to keep crop pests under control and those making more damages of crop pests caused by wrong cropping systems, crop distributions or extensive cultivation, were given and analyzed. From these, two pieces of experience were enlightened as follows： the first, the refoms of cropping systems and crop distributions must be beneficial to pest control or at least not increase the damage of crop pests; the second, we should further clarify the relationship between population dynamics of pests and cropping system/crop distribution, the basis for correctly laying down the ecological regulation systems.     

油田含聚废水处理方法研究

介绍了JCS净水剂在油田含聚丙烯酰胺污水处理中的应用、基本工艺流程、最佳投加量以及成本。     

一种基于B/S的农业资源综合数据服务系统──通用农业资源数据服务系统开发设计

基于浏览器 /服务器 (B/S)结构的通用农业资源数据库系统 ,将农业统计中常用的 5 0 0多个技术指标分成三大类 ,17个小类 ,基本涵盖了农业生产和管理统计的主要领域 普通用户通过浏览器实现对数据库的组合查询或浏览 ,也可将数据文件下载 系统提供了 9种统计分析方法以及 5种预测方法 ,授权用户可进行数据文件上载 管理员通过浏览器可对数据库进行管理维护     

Bernoulli数模2r和3r的同余式

设{Bn}为Bernoulli数,m、n为自然数,本文证明了同余式(2-22n)B2n≡1-4n ∑mk=1(2n)/(2k)24kB2k (mod 24m 3)与(3-32n)B2n≡2-6n 2∑mk=1(2n)/(2k)32kB2k (mod 32m 1).取m=1,2,得到[5]中宣布的(2-22n)B2n(mod 27)与(3-32n)B2n(mod 35)的简单同余式.     

金属在福州地热水中的腐蚀热力学研究──(I)、铜—地热水系统

作者从热力学角度以电位－ｐＨ图探讨金属在福州地热水中的腐蚀趋势．本文报导铜－地热水系统，采用ＢＡＳＩＣ语言编制程序在ＡＰＰＬＥ－Ⅱ微机上计算高温热力学数据，并以ＤＸＹ－８００绘图仪绘制电位－ｐＨ图．同时，测定了铜在福州Ｇｗ２井地热水中的实际腐蚀电位．结果表明：在此地热水中，当温度低于３１８Ｋ，铜表面生成Ｃｕ２Ｏ膜，高于３１８Ｋ，生成ＣｕＯ膜，二者都位于钝化区．     

钠快离子导体Na_(2.5)Zr_(2-x)Ti_xSi_(1.5)P_(1.5)O_(12.0)系统的研究

钠快离子导体Ｎａ_２．５Ｚｒ_２－ｘＴｉ_ｘＳｉ_１．５Ｐ_１．５Ｏ_１２．０系统ｘ＝０－２．０的化合物，由Ｎａ_３ＰＯ_４－ＺｒＯ_２－ＺｒＰ_２Ｏ_７－ＳｉＯ_２－ＴｉＯ_２为反应的起始原料，在９００℃－１２００℃的高温下反应数小时至二十小时制得。系统化合物的相变关系已探明，并测定了有关的单纯相在不同温度下的导电率以及电导激活能。相当于起始组成为Ｎａ_２．５Ｚｒ_１．０Ｔｉ_１．０Ｓｉ_１．５Ｐ_１．５Ｏ_１２．０的单纯相（标为２．５１相）在３００℃时的导电率σ３００＝１．８５×１０－２（Ω·ｃｍ）－１，其电导激活能为２３．６４ｋＪ／ｍｏｌｅ，相当于起始组成为Ｎａ_２．５Ｔｉ_２．０Ｓｉ_１．５Ｐ_１．５Ｏ_１２．０的单纯相（标为２．５２相）在３００℃时的导电率σ３００＝０．４６×１０－２（Ω·ｃｍ）－１，其电导激活能为２８．８９ｋＪ／ｍｏｌｅ．     

Functional magnetic resonance imaging of amphetamine craving

The aim of this study is to identify the brain activity associated with amphetamine craving for understanding the neurobiology of addiction by watching pictures of happy, sad or amphetamine. Brain activity was measured in 12 amphetamine addicts and 12 healthy subjects by fMRI while the subjects watched pictures designed to elicit happy feelings, sad feelings, or the desire to use amphetamine. The result demonstrated that amphetamine cues led to abnormally high cingulate and low frontal lobe activation in amphetamine addicts, who showed abnormalities in affect-related brain activation.     

An ERP study for the degrees of the difficulty in visual search

The present study mainly probed the relationships between ERP components and the degrees of difficulty in visual search. Three experimental and one controlled conditions were randomly selected. Results showed that the P1, N1, and P2 amplitudes and latencies had no significant differences among the three experimental and one controlled conditions, and the ERP waveforms of low perceptual load of visual search were different from that of high perceptual load. These results might indicate that the latencies and amplitudes of initial P1, N1 and P2 in high and low perceptual load conditions were almost the same. The ERP waveforms of parallel search were very different from that of serial search, and the ERP waveforms of serial search were very similar. The P3 amplitudes increased as the degrees of the difficulty in visual search decreased.     

固化盐渍土的自生体积稳定性

为避免盐渍土在固化过程中可能发生的体积变形危害,研究其自生体积稳定性。制备了290mm长的试件,利用高精度位移测量系统,测试了不同含量的氯盐与硫酸盐在不同固化剂体系下引起的固化土的线性膨胀/收缩率,分析了C a2 、N a 以及含水率对膨胀/收缩率的影响。结果表明:固化氯盐盐渍土不会发生较大的体积变形,而固化硫酸盐盐渍土可能引起巨大的膨胀率;采用矿渣-粉煤灰-水泥复合固化剂,参与化学反应而产生膨胀性产物的C a2 减少,可以降低固化盐渍土的膨胀率。当C a2 不足而N a 充分时,氯盐和硫酸盐不会对化学反应起促进作用。含水率会影响固化土结构的疏密程度以及膨胀性产物的生长位置。