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971.
温度对化学反应速度、平衡与转化率的影响 总被引:2,自引:0,他引:2
从热力学和动力学两方面统一起来讨论温度对化学反应速度和化学平衡的影响。 相似文献
972.
The paper establishes a sufficient condition for the controllability of semilinear mixed Volterra–Fredholm-type integro-differential inclusions in Banach spaces. We use Bohnenblust–Karlin's fixed point theorem combined with a strongly continuous operator semigroup. Our main condition (A5) only depends upon the local properties of multivalued map on a bounded set. An example is also given to illustrate our main results. 相似文献
973.
This paper presents a new method for the performance evaluation of bit decoding algorithms. The method is based on estimating the probability density function (pdf) of the bit log likelihood ratio (LLR) by using an exponential model. It is widely known that the pdf of the bit LLR is close to the normal density. The proposed approach takes advantage of this property to present an efficient algorithm for the pdf estimation. The moment matching method is combined with the maximum entropy principle to estimate the underlying parameters. We present a simple method for computing the probabilities of the point estimates for the estimated parameters, as well as for the bit error rate. The corresponding results are used to compute the number of samples that are required for a given precision of the estimated values. It is demonstrated that this method requires significantly fewer samples as compared to the conventional Monte-Carlo simulation. 相似文献
974.
Ravjit Kaur Sabharwal Parduman Singh M. M. Arora B. L. Somani Vivek Ambade 《Indian journal of clinical biochemistry : IJCB》2008,23(1):71-75
The prevalence of microalbuminuria was assessed in 174 albustix negative hypertensive patients by estimating albumin in the
morning random urine samples by immunoturbidimetric method within four hours of voiding of urine. The urine samples were not
stored and collected without any preservatives. The urinary albumin was calculated in terms of ratio with respect to urinary
creatinine and expressed as albumin creatinine ratio (mg/g). Out of 174 albustix negative hypertensives, 58 (33.3%) patients
were found to have microalbuminuria. The prevalence of microalbuminuria in males and females was found to be 34% and 30.7%
respectively. No correlation was found between the Body Mass Index (BMI) and albumin excretion (r2 = 0.0271) and between duration of hypertension and urinary albumin excretion (r2 = 0.0042). Prevalence of microalbuminuria in nonsmokers and non-alcoholic hypertensives was 20%. The prevalence in alcoholics,
smokers and both smokers and alcoholics was found to be 35%, 42% and 41% respectively. The high prevalence of microalbuminuria
than the various reported studies on the subject demands establishment of a screening programme for microalbuminuria, implementation
of specific intervention methods and education of hypertensive patients about the consequences of smoking and alcohol on possible
involvement of renal system. 相似文献
975.
976.
我国煤炭供需方面的基本情况是产量不断增加,增幅有所减缓,供需基本平衡.我国煤炭供需方面存在的主要问题是资源短缺的矛盾日益突出,煤炭运力较为紧张,煤炭回采率低,资源浪费严重.企业安全投入不足,煤炭消费的环境压力较大,煤炭企业工程技术人员短缺,煤炭价格偏低.由于我国资源特点是富煤少油.我们在能源消费上必须坚持以煤为主.我们要实现能源的可持续发展,就必须坚持生态友好型发展原则,努力推进煤炭企业技术进步,发展洁净煤技术,积极推进大型煤炭基地建设和煤炭企业整合.要加大资金投入力度,提高煤矿安全生产水平,积极推进煤电联动.逐步提高煤炭价格,政策上要鼓励煤炭进口,以期实现能源的可持续发展. 相似文献
977.
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979.
980.
把经典分析数学中,连续函数的微积分基本定理、牛顿—莱布尼兹公式,推广到了对任一黎曼可积函数仍成立,在理论上肯定了任一黎曼可积函数都存在连续的广义原函数,并给出了求连续的广义原函数的一般方法. 相似文献