不同热解温度生物炭改良铅和镉污染土壤的研究

 为了探究热解温度对生物炭修复重金属污染土壤的影响,将300℃、500℃和700℃下制备的生物炭加入铅（Pb）和镉（Cd）污染土壤进行培养,检测重金属形态的变化。结果表明,加入生物炭培养60d后,Pb和Cd污染土壤pH值较对照上升0.35—0.86单位值,土壤中重金属的酸可提取态含量下降,残渣态含量上升,对目标重金属生物有效性降低的改良效果700℃>500℃>300℃;在生物炭添加量相同的情况下,复合污染土壤中Pb的残渣态含量比对应单一污染高50.60%—72.79%,而复合污染土壤中Cd的酸可提取态含量较对应单一污染高7.53%—12.99%;热解温度影响生物炭的表面特征和吸附重金属机制,进而影响生物炭改良土壤中目标重金属形态分布。     

Model evaluations for winter orographic clouds with observations

The Real-Time Four-Dimensional Data Assimilation (RT-FDDA) system is used for orographic snowpack enhancement.The model has three nested domains with the grid spacing of 18,6 and 2 km.To evaluate the simulations of winter orographic clouds and precipitation,comparisons are made between model simulations and observations to determine how the model simulates the cloud distribution,cloud height,cloud vertical profiles and snow precipitation.The simulated results of the 02:00 UTC cycling with 2-km resolution are used in the comparison.The observations include SNOTEL,ceilometer,sounding and satellite data,from the ground to air.The verification of these observations indicates that the Weather Research and Forecast (WRF) RT-FDDA system provides good simulations.It is better to use data within the forecast period of 2-16 h simulations.Although the horizontal wind component near the ground has some bias,and the simulated clouds are a little higher and have a little more coverage than observed,the simulated precipitation is a little weaker than observed.The results of the comparison show that the WRF RT-FDDA model provides good simulations and can be used in orographic cloud seeding.     

分光光度法检测不同地区和类型稻种功能性成分的初步研究

 为研究不同地区和类型水稻品种糙米中γ-氨基丁酸和总黄酮等功能性成分,本实验采用分光光度法准确测定了中国、日本、韩国、国际稻作所和云南品种及云南野生稻γ-氨基丁酸和总黄酮的含量.结果表明:① 用分光光度法测定水稻籽粒中γ-氨基丁酸和总黄酮含量的方法是可靠的;② 不同地区和类型水稻品种功能成分含量存在差异;③ 相关分析表明,氨基丁酸与总黄酮的相关系数较高(r=0.575^**),在育种上可以实现多个相关性状间的遗传改良;④ 鉴定出墨江黄皮饵块谷、明恢86、墨江饵块谷、疣粒野生稻等18份高GABA和高总黄酮的水稻品种,可作为选育高黄酮和γ-氨基丁酸品种的亲本或直接作为功能稻开发利用.首次报道疣粒野生稻总黄酮质量分数达0.751%,在所有水稻品种中黄酮含量最高.     

基于块背景建模的运动目标检测

运动目标检测是计算机视觉中目标识别、目标跟踪和场景理解的前提.文中提出一种基于块的混合高斯背景建模方法,采用图像块的均值和块内方差作为块的特征对场景进行建模,并对前景块根据它的邻域块处理以得到更精确的目标区.新方法不仅考虑了像素在时间域上的分布信息,还利用了像素邻域间的信息消除虚警数,改善了传统混合高斯背景建模方法处理...     

新弱化缓冲算子的构造及其运用

将已有的弱化缓冲算子进行一些简单的数学运算后构造出新的弱化缓冲算子.在预测工作中如果系统行为数据出现前阶段增长(衰减)速度过快而后阶段增长(衰减)速度过慢的,以文章所构造的弱化缓冲算子再建模预测能使预测精度有显著提高,预测值也能更好的逼近观测值.     

论建筑工程的施工管理对成本核算的重要性

文章对工民建工程的施工管理到成本核算进行了较为完整的阐述,对当前工民建工程施工管理现状及存在的问题进行了分析、对比,并结合实际提出了管理的相关措施,阐述了从施工管理上下功夫对降低成本是一种有效的方法。     

科学证据、类比方法和伦理论证——兼论严重脑损伤患者的他心问题

以类比论证来确认他心认识的可能性与途径的研究方法曾经受到许多哲学家的诟病。继人工语言哲学家的工作之后,日常语言哲学家将他心问题从一种单纯的认识论问题转化为日常生活中的沟通问题,从而使他心问题部分地得到解决。不过,陷入昏迷状态的脑损伤患者是否具有思想、情感以及其他心理属性等仍然是一个悬而未决问题。神经科学对大脑活动与意识状态之间的关联性研究推进了这一领域的进展。在此基础上,有研究者试图运用类比的方法,结合大脑活动与意识状态之间关联性的研究结果,论证他者具备意识能力和心理属性,进而探讨对待他者道德义务的有效性问题。神经科学的研究拓展了我们对于大脑和意识的认识,但是对他者负有道德义务并不必然要求他者具备意识能力,同时论证和论据存在内在缺陷。神经科学对他心问题的解答存在局限性。     

采用决策树分类方法进行煤矸石信息提取研究

利用遥感技术快速、准确地调查煤矸石堆分布情况,对预防地质灾害以及保护生态环境和居民生命财产安全有着重要的指导意义.基于TM多光谱影像,运用知识决策树分类方法对江西萍乡煤矿区进行煤矸石信息提取试验.首先,在研究区背景知识的基础下,统计分析矿区内煤矸石及其他典型地物在影像上的光谱特征,建立了研究区的分类知识库;其次,在决策...     

Tumour evolution inferred by single-cell sequencing

Genomic analysis provides insights into the role of copy number variation in disease, but most methods are not designed to resolve mixed populations of cells. In tumours, where genetic heterogeneity is common, very important information may be lost that would be useful for reconstructing evolutionary history. Here we show that with flow-sorted nuclei, whole genome amplification and next generation sequencing we can accurately quantify genomic copy number within an individual nucleus. We apply single-nucleus sequencing to investigate tumour population structure and evolution in two human breast cancer cases. Analysis of 100 single cells from a polygenomic tumour revealed three distinct clonal subpopulations that probably represent sequential clonal expansions. Additional analysis of 100 single cells from a monogenomic primary tumour and its liver metastasis indicated that a single clonal expansion formed the primary tumour and seeded the metastasis. In both primary tumours, we also identified an unexpectedly abundant subpopulation of genetically diverse 'pseudodiploid' cells that do not travel to the metastatic site. In contrast to gradual models of tumour progression, our data indicate that tumours grow by punctuated clonal expansions with few persistent intermediates.