爱若琴弦

66岁的她静静地站着。“这是我在这个世界里的最后一天了,等到今天过去,我会永远的离开这个世界。”她这样想着,并留恋地看着自己的影子、自己亲手一砖一瓦建起来的城邦和曾经每天陪着自己练功的那150个女仆。“不要再想了,都已经决定了的事。”她勉强地给自己一个笑容。“直的决定了吗?”他问。     

Carbon sequestration within millet phytoliths from dry-farming of crops in China

Phytoliths are noncrystalline minerals that form inside cells and cell walls of different parts of plants. Organic carbon in living cells can be occluded in phytoliths during plant growth. It has been documented that the occluded carbon within phytoliths is an important long-term terrestrial carbon reservoir that has a major role in the global carbon cycle. Common millet and foxtail millet have become typical dry-farming crops in China since the Neolithic Age. The study of carbon conservation within phytoliths in these crops could provide insights into anthropogenic influences on the carbon cycle. In this study, we analyzed the carbon content in phytoliths of common millet and foxtail millet. The results indicated that (1) common millet and foxtail millet contained 0.136% ± 0.070% and 0.129% ± 0.085% phytolith-occluded carbon (PhytOC) on a dry mass basis, respectively; (2) based on the mean annual production of common millet and foxtail millet in the last 10 years, the phytolith occluded carbon accumulation rate of common millet and foxtail millet was approximately 0.023 ± 0.015 and 0.020 ± 0.010 t CO 2 ha 1 a 1 , respectively; (3) assuming a similar phytolith occluded carbon accumulation rate as for common millet (the highest accumulation rate was 0.038 t CO 2 ha 1 a 1 ), this could result in the sequestration of 2.37 × 10 6 t CO 2 per year for the 62.4 × 10 6 ha dry-farming crops in China. Although there was a decline in the annual production rate and planting area of foxtail millet during 1949 to 2008, the total phytolith carbon sequestration rate was 7×10 6 t CO 2 within the 60-year period. However, phytolith occluded carbon has not yet been fully considered as a global carbon sink. Also, this carbon fraction is probably one of the best candidates for the missing carbon sink.     

异丁基硼酸的超声辐射合成

在超声条件下,以卤代烃、金属镁粉、硼酸酯为原料合成了异丁基硼酸.反应的最佳条件为:以碘及二溴乙烷做催化剂,超声波功率为175 W,反应时间为15 min,反应温度为40℃.     

Plankton from Early Cambrian black shale series on the Yangtze Platform, and its influences on lithologies

Blackshalesandcherts ,containingnodularphosphoritesandorelayers[1] arecommonintheEar lyCambriandeeperwaterfaciesoftheYangtzePlat form[2 ] andoffera goodchanceformicropaleonto logicalresearchusingtechniquesofchemicaldissolu tion ,peelingandsectioning .Wetriedtoseparateandinvestigateoceanicplanktoncommunitiesfrombitu minous,“deeperwater”chert ,blackshale andphosphoritelithologies ,andtodocumenttheirpreser vationandinfluencesonthecompositionofthesedi ments .Thepresentpaperaimsatgivingareportof…     

Biore mediation: A review of applications and problems to be resolved

Bioremediationisaformofbiotechnologyhavingthecharacteristicsoflowenergyconsumption ,highefficiencyandhighenvironmentalsafety ,whichcandegradeandremoveenvironmentalpollutantsbythephysicalmetabolismofthebacteria ,fungi,higherplantsandcellularfreeenzymes.Inabroadsense ,bioremediationconsistsofthreemaincategories ,namely :themicrobialremediation ,thephytoreme diationandthecellularfreeenzymeremediation .Asachallengingleadingedgetechnology[1] ,bioremedia tionhasmovedintoaflourishingera .Itisanticipa…     

用改进的一点配置法计算催化剂有效因子

采用本文第（Ⅰ）报提出的计算多孔催化剂有效因子的方法,针对三种不同形状的催化剂颗粒,对幂函数型动力学方程和双曲动力学方程进行了大量的计算,采用改进的一点配置法所得得计算结果与正交配置解符合。改进的一点配置法的优点是使用简便,计算快速。采用改进的一点配置法还可以计算催化剂颗粒“死区”半径。并且计算结果合理。     

一种基于兴趣挖掘的机会网络内容分发策略

提出了一种新的墓于兴趣挖掘的机会网络内容分发策略(Interest Mining Based Scheme,IMBS),通过贝叶斯理论分析节点的兴趣以及节点墓于兴趣的相遇频率,挖掘移动节点随机运动背后所蕴含的人类社交特征和情感特征此外,IMBS采用发布/订阅机制,收集节点的订阅信息,以获取消息在整个网络中的需求量在转发消息的时候,IMBS把消息的需求总量和节点的情感特征以及社交特征结合起来选择下一跳节点仿真实验及算法复杂度分析表明,在不提高算法复杂度的情况下,IMBS可显著减少消息的传输延时和网络开销,并提高消息传输的成功率     

Establishment and cryopreservation of liver, heart and muscle cell lines derived from the Chinese alligator （Alligator sinensis）

The Chinese alligator, Alligator sinensis, is a critically endangered species. A conservation project of gene resources for an endangered species first involves the preservation of organs, tissues, gametes, genomic DNA libraries and cell lines. The present study is the first to establish and cryopreserve cell lines of liver, heart and muscle tissues from the Chinese alligator. The study revealed that there was a large discrepancy in cell migration time in primary cultures among liver (11-12 d), heart (13-14 d) and muscle (17-18 d) tissue pieces. The differences in time in primary cell culture suggested that it was relatively easy to build visceral-derived cell lines for reptiles. Biological analysis showed that the population doubling time for thawed cells was approxi- mately 36 h. Karyotyping revealed that the frequency of Chinese alligator cells showing chromosome number as 2n=32 was 88.6%-93.4%. Chinese alligator cell lines established here provide a vital resource for research and are likely to be useful for protection of this rare and critically endangered species. Furthermore, the establishment of these methods may supply technical and theoretical support for preserving genetic resources at the cellular level for other reptile species.     

Experimental study on the explosive boiling in saturated liquid nitrogen

Nowadays,thedevelopmentandapplicationofsuperconductionisbecomingmoreandmoreimpor tantinmanyareas .Duringtheworkingprocessofsu perconductor,somefactors ,forinstance ,deforma tion ,friction ,andmagneticvortex ,canresultinin stantaneousandrandomheatimpulsion ,andmakeitover heatedtothecriticaltemperatureanddeviatefromthenormaloperationcondition .Undersomeex tremeconditions ,thesuperconductorcannotgobacktothenormalstateevenifremovingthetransientheat load ,thusverysevereandunexpectableconse quencema…