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901.
利用中药渣栽培平菇高产技术探讨 总被引:1,自引:0,他引:1
报告了利用中药渣为主料,以木屑埋菌棒方式栽培平菇的生产技术。结果表明:这种方法可就地取材,成本低,质量好,产量高。 相似文献
902.
本文建立了一套热模拟试验方法,获得了初始凝固过程3s之内的坯壳;提出了考虑固液界面热流的等效凝固潜热计算方法,并据此用一维凝固传热解析法计算出了初始凝固过程的热流分布和传热系数分布,比较和探讨了热顶结晶器材质对初始凝固传热的作用。 相似文献
903.
本文着重阐述了有机体能量代谢过程中ATP—CP系统、有氧氧化和无氧酵解三大供能系统的偶联反应。并对ATP恢复的影响因素作了分析,同时介绍了作者对ATP的再认识和理解。 相似文献
904.
905.
De-ubiquitination and ubiquitin ligase domains of A20 downregulate NF-kappaB signalling 总被引:1,自引:0,他引:1
Wertz IE O'Rourke KM Zhou H Eby M Aravind L Seshagiri S Wu P Wiesmann C Baker R Boone DL Ma A Koonin EV Dixit VM 《Nature》2004,430(7000):694-699
906.
The recent discovery of a pterosaur egg with embryonic skeleton and soft tissues from the Yixian Formation confirmed that the flying pterosaurs were oviparous. Here we describe another pterosaur egg whose exquisite preservation indicates that the shell structure was soft and leathery. 相似文献
907.
江苏省常州市城市地价动态监测信息系统设计与实现 总被引:1,自引:0,他引:1
以常州市为例,介绍地价监测点的设立过程,并对城市地价动态监测信息系统的总体设计思路作具体阐述.系统运用迭代增量法,采用GIS控件MapX进行开发.该系统已在常州市国土资源局局域网上日常运行,并利用地价监测点资料自动编制常州市地价指数,用以分析、预测常州市地价变化的基本趋势,为科学管理和合理利用城市土地资源提供科学依据. 相似文献
908.
ZHUDa MAZhongyuan MEIJiaxin HANPeigao HUANGXinfan CHENKenji 《科学通报(英文版)》2004,49(18):1906-1910
A series of hydrogen-containing a-Si:H/SiO2 multilayers with different a-Si:H sublayer thickness were fabricated by layer-by-layer deposition and in situ plasma oxidation in a plasma-enhanced chemical vapor deposition system (PECVD). Optical induced blue emission from the samples was observed by the naked eye at room temperature, which has never been reported in the luminescence study of Si/SiO2 multilayers up to now. Both the photoluminescence (PL) peak and the absorption edge show a blue shift as the a-Si:H sublayer thickness decreases. The origin of the blue emission and the effect of hydrogen are discussed. 相似文献
909.
The outbreak pattern of the SARS cases in Asia 总被引:1,自引:1,他引:0
ZHANGZhibin SHENGChengfa MAZufei LIDianmo 《科学通报(英文版)》2004,49(17):1819-1823
The severe acute respiratory syndrome (SARS) caused tremendous damage to many Asia countries, especially China. The transmission process and outbreak pattern of SARS is still not well understood. This study aims to find a simple model to describe the outbreak pattern of SARS cases by using SARS case data commonly released by governments. The outbreak pattern of cumulative SARS cases is expected to be a logistic type because the infection will be slowed down due to the increasing control effort by people and/or due to depletion of susceptible individuals. The increase rate of SARS cases is expected to decrease with the cumulative SARS cases, as described by the traditional logistical model, which is widely used in population dynamic studies. The instantaneous rate of increases were significantly and negatively correlated with the cumulative SARS cases in mainland of China (including Beijing, Hebei, Tianjin, Shanxi,the Autonomous Region of Inner Mongolia) and Singapore. The basic reproduction number R0 in Asia ranged from 2.0 to 5.6 (except for Taiwan, China). The R0 of Hebei and Tianjin were much higher than that of Singapore, Hongkong, Beijing, Shanxi, Inner Mongolia, indicating SARS virus might have originated differently or new mutations occurred during transmission. We demonstrated that the outbreaks of SARS in many regions of Asia were wall described by the logistic model, and the control measures implemented by governments are effective. The maximum instantaneous rate of increase, basic reproductive number, and maximum cumulative SARS cases were also calculated by using the logistic model. 相似文献
910.
In this work, we made progress on the problem that [ symbol: see text] is a Banach algebra under schur product. Our results extend Tonge's results. We also obtained estimates for the norm of the random quadralinear form A:l(r)(M) x l(p)(N) x l(q)(K) x l(s)(H)-->C, defined by: A(e(i), e(j), e(k), e(s))=a(ijks), where the (a(ijks))'s are uniformly bounded, independent, mean zero random variables. We proved that under some conditions [ symbol: see text] is not a Banach algebra under schur product. 相似文献