摘要：高镍层状氧化物是电动汽车高能量密度锂离子电池正极材料的首选。本文通过第一性原理计算模拟了Li_(1-x)NiO_(2-y)S_y材料的脱锂过程。通过GGA+U计算分析了体系费米能级处的电子结构,充电过程中的氧化还原机制和热稳定性。在Li_(1-x)NiO_(2-y)S_y脱锂过程中,首次发现硫参与电荷补偿,抑制过渡金属的迁移,降低晶格扭曲幅度和提高体系中氧的稳定性。这种基于硫阴离子氧化还原对锂离子电池阴极材料电化学行为的调制有助于设计高稳定性的高镍正极材料。

摘要：除雾器是湿法烟气脱硫系统关键设备之一,其性能直接影响脱硫系统甚至机组的安全运行。以某660 MW燃煤机组双塔双循环脱硫系统除雾器堵塞并导致部分模块掀翻故障为例,对影响除雾器性能的空塔流速、安装空间、冲洗水压等设计因素,入口烟尘浓度,除雾器冲洗水量,浆液、石膏及结垢物成分等进行了全面分析。结果表明:脱硫系统水平衡控制不当以及二级塔pH值控制偏高是除雾器故障主要原因。为降低除雾器运行风险,针对双塔双循环脱硫系统水平衡和浆液pH值控制,给出了合理建议。

摘要：随着深度学习的快速发展,相关算法被广泛应用于量子化学计算领域以实现高效的分子设计及性质研究,其中,多任务学习方法通过挖掘分子性质之间的关系可以同时预测多个分子属性,然而此类研究目前较为有限.本文采用硬参数共享结构与损失函数加权方法来实现多任务分子性质预测.通过对比单任务基准与各类多任务模型在不同分子属性集上的性能,展示了多属性预测精度强烈依赖于属性间的关系,当关联变复杂时,硬参数共享可以提高预测精度,此外,恰当的损失函数加权方法有利于实现更均衡的多目标优化,使预测更准确.进一步的实验展示了多任务学习模型的计算效率优势及其在训练数据量受限时的预测性能优势.

摘要：Vinblastine has been used clinically as one of the most potent therapeutics for the treatment of several types of ***,the traditional plant extraction method suffers from unreliable supply,low abundance,and extremely high ***,we use synthetic biology approach to engineer Saccharomyces cerevisiae for de novo biosynthesis of vindoline and catharanthine,which can be coupled chemically or biologically to *** the basis of a platform strain with sufficient supply of precursors and cofactors for biosynthesis,we reconstituted,debottlenecked,and optimized the biosynthetic pathways for the production of vindoline and *** vindoline biosynthetic pathway represents one of the most complicated pathways ever reconstituted in microbial cell *** shake flask fermentation,our engineered yeast strains were able to produce catharanthine and vindoline at a titer of 527.1 and 305.1μg·liter^(−1),respectively,without accumulating detectable amount of pathway *** study establishes a representative example for the production of valuable plant natural products in yeast.

摘要：提出了一种用于中波红外成像的基于15位像素级单斜率模数转换器的低功耗数字读出电路。像素级模数转换器采用一种新型功耗自适应的脉冲输出型比较器,只有当斜坡电压信号接近积分电压时,比较器才产生功耗。此外,比较器输出脉冲信号,降低了15位量化结果存储器上消耗的动态功耗。该存储器采用三管动态结构,仅占约54μm^(2)面积,以满足15μm像素中心距的面积约束。量化结果以电流模式读出到列级,避免相邻列总线间的电压串扰。基于0.18μm CMOS工艺,采用该结构,设计并制造了640×512规格的数字读出电路。测试结果表明,在120 Hz的帧频下,功耗仅为48 mW,总积分电容为740 fF,电荷处理能力为8.8 Me^(-)。在满阱状态,等效到积分电容的噪声电压为116μV,峰值信噪比为84 dB。

摘要：等离激元共振产生的高能热载流子可以降低反应能垒,加速特定的电化学反应.然而,绝大多数研究聚焦于热电子的高效利用,对于热空穴,特别是带间激发的热空穴在光增强电氧化反应(PEEO)中的作用尚缺乏研究.本文以金纳米三角结构作为电催化剂,解析了带间和带内跃迁激发的热空穴对电催化乙醇氧化反应的贡献.研究发现,尽管带内跃迁的消光截面是带间跃迁的5倍,但由于d带热空穴具有更高的氧化电势,带间激发对电催化乙醇氧化反应过程具有更高的催化活性,展示出更高的电流密度和更低的起峰电势.根据光照前后电化学反应活化能和起峰电位,进一步建立了估算PEEO中热空穴贡献的方法.定量分析结果表明,带间激发热空穴的相对光电化学转换效率比带内激发高12倍,证明d带热空穴在PEEO中具有更高的反应活性.本工作不仅揭示了PEEO中热空穴的详细作用机制,且对于高效设计等离激元共振电催化剂有重要意义.

摘要：Probiotics are the treasure of the microbiology *** have been widely used in the food industry,clinical treatment,and other *** equivocal health-promoting effects and the unknown action mechanism were the largest obstacles for further probiotic’s developed *** recent years,various genome editing techniques have been developed and applied to explore the mechanisms and functional modifications of *** important genome editing tools,CRISPR-Cas systems that have opened new improvements in genome editing dedicated to *** high efficiency,flexibility,and specificity are the advantages of using CRISPR-Cas ***,we summarize the classification and distribution of CRISPR-Cas systems in probiotics,as well as the editing tools developed on the basis of ***,we discuss the genome editing of probiotics based on CRISPR-Cas systems and the applications of the engineered probiotics through CRISPR-Cas ***,we proposed a design route for CRISPR systems that related to the genetically engineered probiotics.

摘要：为了对中国云南省金平县地区隐伏磁铁矿体进行探测,使用多旋翼无人机对7.8 km^(2)的目标区域进行航磁测量,克服了该地区高海拔、地形崎岖、植被茂密等带来的地面勘查困难。通过现场试验对观测噪声来源与噪声水平进行研究。然后,将质子磁力仪置于距离多旋翼无人机下方3 m处位置以减小静态噪声。提出非线性滤波与逆距离加权插值算法以抑制由强风导致的动态噪声。结果表明,这些方法能减缓无人机旋翼和强风的干扰,经过处理的实测航磁数据与已知地层的水平分布吻合良好。根据航磁测量结果,在布置的4口钻井中都勘测到了隐伏的钛磁铁矿,证明旋翼无人机航磁测量找矿的有效性。

摘要：The datasets of the Chinese Academy of Sciences(CAS)Flexible Global Ocean–Atmosphere–Land System(FGOALS-f3-L)model for the baseline experiment of the fully coupled runs in the Diagnostic,Evaluation and Characterization of Klima(DECK)common experiments of phase 6 of the Coupled Model Intercomparison Project(CMIP6)are described in this *** CAS FGOALS-f3-L model team submitted the pi Control run with a near equilibrium ocean state for 561 model years,and 160-year integrations for three ensemble members of abrupt-4×CO2 and 1pct CO2,*** ensemble members restart from the 600,650 and 700 model years in the pi Control run,*** baseline performances of the model are validated in this *** preliminary evaluation suggests that the CAS FGOALS-f3-L model can preserve the long-term stability well for a mean net radiation flux of 0.31 W m-2at the top of the atmosphere,and a limited decreasing trend of-0.03 W m-2/100 *** global annual mean SST is 16.45°C for the 561-year mean,with an increase of 0.03°C/100 *** model captures the basic spatial patterns of climate-mean SST and precipitation,but still underestimates the SST over the warm *** coupled model mitigates the precipitation bias in the ITCZ compared with the results from ***,the model’s climate sensitivity represented by the equilibrium climate sensitivity has been reduced from 4.5°C in CMIP5 to 3.0°C in *** these datasets contribute to the benchmark of model behaviors for the desired continuity of CMIP.

摘要：TiFeSb是一种以half-Heusler结构为主相的多相材料.在这项工作中,我们发现可以通过将Ni填充到half-Heusler结构的4d空位来稳定TiFeSb,并获得单相TiFeNi_(0.1)Sb合金.为了提高热电性能,我们设计并合成了具有更多价电子的TiFe_(1.1−x)Ni_(x)Sb(x=0.1–1.0)样品.结构分析表明,x=0–0.3的样品是具有类half-Heusler结构的单相合金,x=0.4–0.7的样品是以Double half-Heusler为主相的两相材料,x=0.8–1.0的样品是类full-Heusler结构的单相材料.同时,在TiFe_(1.1−x)Ni_(x)Sb中实现了优异的p型(x=0–0.3)和n型(x=0.8–1.0)电输运性能,这可以用Slater-Pauling规则很好地解释.结合由于无序晶体结构而大大降低的晶格热导率,p型TiFe_(0.8)Ni_(0.3)Sb和n型TiFe_(0.3)Ni_(0.8)Sb在973 K下分别获得了约0.6和0.4的热电优值.我们还证明,这些样品的热电性能可以通过常规掺杂或合金化方法进一步优化.通过Cu代替Ni(或Fe),p型TiFe_(0.8)Ni_(0.2)Cu_(0.1)Sb的载流子浓度降低,并且在973 K时热电优值达到0.8,这是空位填充型Heusler合金的最高记录.