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基于COMSOL的四极质谱离子运动仿真研究

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真空科学与技术学报 2017年第9期37卷 873-877页

作者：时仪王国栋陈长琦乔路张棋卢耀文延峰合肥工业大学真空科学与装备工程系合肥230009 北京东方计量测试研究所北京100089

四极杆质量分析器(即四极质谱仪)因其结构简单、价格较低,被广泛应用于各分析测量领域。围绕着四极杆质量分析器的使用要求,基于四极场离子运动理论基础,结合粒子碰撞理论,利用有限元分析软件COMSOL对四极场电压进行了仿真模拟。结合电... 详细信息

四极杆质量分析器(即四极质谱仪)因其结构简单、价格较低,被广泛应用于各分析测量领域。围绕着四极杆质量分析器的使用要求,基于四极场离子运动理论基础,结合粒子碰撞理论,利用有限元分析软件COMSOL对四极场电压进行了仿真模拟。结合电场仿真的结果,对四极场中离子轨迹进行了仿真研究。仿真分析了压强大小以及a、q值对离子轨迹和通过率的影响。结果表明四极杆质量分析器应在低于10-2Pa压强下运行。在q值不变情况下,a值的增大会导致通过率降低,另外,q值大小对离子通过率也有较大影响。仿真结果为探索四极杆质量分析器的研制可提供理论和技术上的支持。

关键词：四极场碰撞离子轨迹压强

不同降压速率下天然气水合物垂直井分段降压开采特性试验研究

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岩土力学 2024年第9期45卷 2682-2694页

作者：蒋宇静颜鹏栾恒杰刘明康梁伟杜晓宇马先壮史一辰山东科技大学矿山灾害预防控制省部共建国家重点实验室培育基地山东青岛266590 山东科技大学能源与矿业工程学院山东青岛266590 长崎大学工学研究科日本长崎中国矿业大学深部岩土力学与地下工程国家重点实验室江苏徐州221116 新加坡国立大学土木与环境工程系新加坡

认识分段降压法对天然气水合物储层开采特性的影响规律,能够为提高天然气水合物开采的效率和可控性提供科学依据。为此,利用自主研发的大尺寸二维天然气水合物开采模拟试验装置,开展了3种不同降压速率下的天然气水合物单一垂直井分段降... 详细信息

认识分段降压法对天然气水合物储层开采特性的影响规律,能够为提高天然气水合物开采的效率和可控性提供科学依据。为此,利用自主研发的大尺寸二维天然气水合物开采模拟试验装置,开展了3种不同降压速率下的天然气水合物单一垂直井分段降压开采模拟试验,研究了降压速率对降压开采过程中储层的压力响应、温度响应、产气量、瞬时产气速率以及平均产气速率等的影响情况。结果表明:压力变化速率的异常峰值现象的产生与回压阀密切相关,且其持续时间之比约等于降压速率的反比;相同降压幅度下,降压速率越小时,降压持续的时间越长,外部热量传递越多,促使更多的水合物在降压阶段发生分解,使得总产气占比越高;随着降压速率减小,峰值产气速率在第2次降压阶段内出现的时间越来越晚,水合物分解速率达到最大值的时间逐渐推后。

关键词：天然气水合物分段降压降压速率温压响应产气特性

Metabolome and RNA-seq reveal discrepant metabolism and secretory metabolism profile in skeletal muscle between obese and lean pigs at different ages

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Science China Life Sciences 2025年

作者： Liu Guo Junfei Xu Wenyue Zhou Sisi chen Hanjing shi Mengmeng Han Zekun Yang Yehui Duan Weijun Pang Yulong yin Fengna Li Laboratory of Animal Nutritional Physiology and Metabolic Process Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences University of Chinese Academy of Sciences Laboratory of Animal Fat Deposition and Muscle Development College of Animal Science and Technology Northwest A&F University College of Advanced Agricultural Sciences University of Chinese Academy of Sciences

Metabolites and metabolism-related gene expression profiles in skeletal muscle change dramatically under obesity, aging and metabolic disease. Since obese and lean pigs are ideal models for metabolic research. Here, we compared metabolome and transcriptome of Longissimus dorsi(LD) muscle between Taoyuan black(TB, obese) and Duroc(lean) pigs at different ages. We defined the “window phase” of intramuscular fat(IMF) deposition in TB pig, which has significantly higher IMF than Duroc pig. Our results displayed discrepant lipid composition and different expression genes(DEGs) enriched in lipid metabolism, and both metabolome and transcriptome analyses revealed stronger energy expenditure and more active amino acid and protein metabolism in Duroc pig. 10 up-and 51 down-regulated biomarker metabolites with age-and breed-specificity were identified. Potential secretory metabolites, including organic acid(fumaric acid, succinate,malic acid, and gamma-aminobutyric acid), amino acid(L-lysine, and L-glutamic acid), lipid(2-hydroxyisovaleric acid, and L-carnitine) were demonstrated a significant correlation with IMF deposition. Our research highlights the huge difference of metabolic spectrum in skeletal muscle between obese and lean model and muscle-derived secretory metabolites might act as an ambassador of intercellular communication to regulate systematic metabolism.

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A versatile synthetic strategy towards rare earth based metal-organic frameworks

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Science China Chemistry 2025年

作者： Quan shi Yun-Hao Xu Ming-Hui chen Peng Zhao Wen-Bo Deng Ji Xiong Kai Guo Ya-Qing Feng Bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry Jieyang Center

Rare earth metal-organic frameworks (RE-MOFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MOFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3COO)6·4H2O) as a precursor to construct RE-MOFs.2D RE-MOFs (RE-DBP) and 3D RE-MOFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MOFs were further synthesized to verify the universality of the *** crystalline RE-MOFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MOFs was investigated in the photocatalytic cycloaddition of CO2with *** the RE-DBP(Co) MOFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MOF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MOFs,but also proposes a promising approach for the potential bulk production of RE-MOFs at room temperature.

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Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan Huang yi-De Zhang Jie chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-yian Guo Jian-Gang Shen Su-Hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

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厌氧颗粒污泥启动及菌群结构变化研究

现代化工 2021年第7期41卷 219-224,227页

作者：王文奇师辰艺刘明庆范梦婕刘济宁陈英文南京工业大学生物与制药工程学院江苏南京210009 生态环境部南京环境科学研究所江苏南京210042

利用升流式厌氧污泥床(UASB),以精对苯二甲酸(PTA)废水为降解对象,在中温条件(30℃)下研究PTA废水方式的启动和葡萄糖方式的启动及菌群结构变化。实验结果表明,葡萄糖启动方式和PTA废水启动方式均可成功启动UASB反应器,葡萄糖启动完成后... 详细信息

利用升流式厌氧污泥床(UASB),以精对苯二甲酸(PTA)废水为降解对象,在中温条件(30℃)下研究PTA废水方式的启动和葡萄糖方式的启动及菌群结构变化。实验结果表明,葡萄糖启动方式和PTA废水启动方式均可成功启动UASB反应器,葡萄糖启动完成后COD去除率在75%左右,TA去除率约为65%;PTA废水启动完成后COD去除率在63%左右,TA去除率在53%左右。通过对比发现,葡萄糖启动方式更容易启动UASB反应器,且降解效率高。对葡萄糖启动方式过后的污泥进行微生物多样性分析发现,门类上,污泥样主要以Chloroflexi(绿弯菌门)、Proteobacteria(变形菌门)、Actinobacteria(放线菌门)和Bacteroidetes(拟杆菌门)为主;而在种属中,污泥样主要以norankfnorankoSBR031、norankfBacteroidetesvadinHA17、Propioniciclava、Anaerolineaceae、Syntrophus、Anaerolinea、Georgenia、Longilinea为主。

关键词：对苯二甲酸 UASB 厌氧颗粒污泥菌群结构

Toward understanding the role of genomic repeat elements in neurodegenerative diseases

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Neural Regeneration Research 2025年第3期20卷 646-659页

作者： Zhengyu An Aidi Jiang Jingqi chen Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence Fudan UniversityShanghaiChina Zhangjiang Fudan International Innovation Center ShanghaiChina

Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements.

关键词： Alzheimer's disease ataxia deep learning long-read sequencing neurodegeneration neurodegenerative diseases Parkinson's disease repeat element structural variant

Scalping or Line-sitting:The Role of Speculators

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Journal of Systems Science and Systems Engineering 2022年第1期31卷 1-33页

作者： Qianqian chen Zhenyang shi yi Yang School of Management Zhejiang UniversityHangzhou310058China

Speculative behaviors have burgeoned in various business settings whereby it is costly for consumers to purchase directly from *** paper examines the values of two typical speculative behaviors,scalping and line-sitting,against a backdrop of markets with *** establish a two-stage model in which a monopolist seller sells an item(product or service)to consumers in the first stage,and the item can be traded on a resale platform in the second *** have no interests in consumption but incur lower costs in pm-chasing and reselling processes than *** the scalping model,they buy the item first and resell it later to make *** the line-sitting model,they earn incomes by serving as surrogates of consumers in *** first find whether the two phenomena emerge critically depends on the value of consumers'entry *** main results indicate that both speculative behaviors can bring benefits to the seller and resale platform by a demand expansion effect,although through different *** scalping,the entry of speculators as additional buyers always boosts demand in both stages,and achieves a win-win outcome for the seller and platform,although less consumers remain in the market and the resale price *** line-sitting,demand is enlarged and profits rise in both stages,only when consumers find purchasing directly more time-and money-consuming,because they need to pay an extra service fee to ***,the consumer population gets better off from the two speculative behaviors when their entry cost is relatively *** both models emerge,scalping may be preferable to line-sitting for the seller,resale platform and consumers,if the cost advantage of speculators in resale transactions is more evident.

关键词： Speculative behavior scalping line-sitting strategic behavior entry cost

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通州湾港区水交换能力提升技术研究

水道港口 2021年第6期42卷 746-752页

作者：高飞施逸辰张长宽河海大学港口海岸与近海工程学院南京210098

通州湾港区拟建南、北两个窄长形的环抱式港池,新规划码头向东延伸约20 km,与南侧的吕四港区形成了仅有东面开口的环抱式港湾。针对拟建南、北两个港池及上述环抱式港湾都将面临着水体交换不足的问题,提出在新建港区北侧围建一块可供创... 详细信息

通州湾港区拟建南、北两个窄长形的环抱式港池,新规划码头向东延伸约20 km,与南侧的吕四港区形成了仅有东面开口的环抱式港湾。针对拟建南、北两个港池及上述环抱式港湾都将面临着水体交换不足的问题,提出在新建港区北侧围建一块可供创造生态湿地的蓄水水域,涨潮时利用闸门开启蓄水;落潮时闭锁闸门使得蓄水水域的水位始终保持在较高水位的状态;蓄水水域的水体则通过水体通道注入新建港池及通州湾内湾,形成穿港流动,将污染水体从港池和港湾排向外海。研究结果显示:采用该方法,无论是拟建的南、北港池还是在通州湾内湾的污染水体均可有效地被排至外海,对比于开通水体通道方法,提升水体交换效果高达49倍。同时,蓄水水域可用于创造生态湿地环境,完美体现海洋资源可持续开发利用的指导思想。

关键词：通州湾环抱式港池穿港流水体通道蓄水水域