检索结果-南通市图书馆

Continuous-flow enzymatic synthesis of chiral lactones in a three-dimensional microfluidic reactor

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第3期35卷 299-303页

作者： xuelei deng Meng Fan Miao Wu Xiaoyan Zhang Ya Cheng Jianye Xia Yingping Zhuang Weiping Zhu Xuhong Qian Yunpeng Bai State Key Laboratory of Bioreactor Engineering Shanghai Collaborative Innovation Center for BiomanufacturingEast China University of Science and TechnologyShanghai 200237China The Extreme Optoelectromechanics Laboratory School of Physics and Materials ScienceEast China Normal UniversityShanghai 200241China Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China

A new continuous-flow process for the enzymatic synthesis of optically pureγ-lactones,which are used as flavors and fragrances in the food and cosmetic industries,was developed in a three-dimensional microfluidic *** microchannels(175 mm in length,0.9 mm in depth,and 1.72 mL in volume)were carved precisely inside a single borosilicate glass(90 mm×75 mm×12 mm)with ultrafast femtosecond laser *** flow field analysis and reaction simulation showed that the mixing of substrates and enzymes was enhanced,allowing the adjustment of residence time in a wide ***_(V4),a carbonyl reductase with excellent catalytic activity and enantioselectivity towardγ/δ-keto acids,was employed for the asymmetric synthesis of various chiral lactones.30 mmol/L(R)-γ-decalactone(3g)can be obtained in 26 s with a space-time yield(STY)up to 16,877 g L^(-1)d^(-1),which is 14.4 times higher than the highest STY of batch reaction reported *** continuous-flow process was applied to the synthesis of 6 chiral *** addition,the scaled-up synthesis of 3g was carried out in 6 cascade microreactors continuously for 6 h,demonstrating the feasibility and stability of the 3D continuous-flow process in enzymatic synthesis of optically pure compounds.

关键词： Continuous-flow Flow chemistry Microreactor Biocatalysis Carbonyl reductase Asymmetric reduction

Distinct roles of H3K27me3 and H3K36me3 in vernalization response, maintenance, and resetting in winter wheat

在线全文

学校读者我要写书评

暂无评论

Science China Life Sciences 2024年第10期67卷 2251-2266页

作者： Xuemei Liu Min deng Bingxin Shi Kehui Zhu Jinchao Chen Shujuan Xu Xiaomin Bie Xiansheng Zhang xuelei Lin Jun Xiao Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of Sciences University of Chinese Academy of Sciences Institute of Science and Technology Austria (ISTA) National Key Laboratory of Wheat Improvement College of Life SciencesShandong Agricultural University Centre of Excellence for Plant and Microbial Science (CEPAMS) JIC-CAS

Winter plants rely on vernalization, a crucial process for adapting to cold conditions and ensuring successful reproduction. However,understanding the role of histone modifications in guiding the vernalization process in winter wheat remains limited. In this study, we investigated the transcriptome and chromatin dynamics in the shoot apex throughout the life cycle of winter wheat in the field. Two core histone modifications, H3K27me3 and H3K36me3, exhibited opposite patterns on the key vernalization gene VERNALIZATION1(VRN1),correlating with its induction during cold exposure. Moreover, the H3K36me3 level remained high at VRN1 after cold exposure, which may maintain its active state. Mutations in FERTILIZATION-INDEPENDENT ENDOSPERM(TaFIE) and SET DOMAIN GROUP 8/EARLY FLOWERING IN SHORT DAYS(TaSDG8/TaEFS), components of the writer complex for H3K27me3 and H3K36me3, respectively, affected flowering time. Intriguingly, VRN1 lost its high expression after the cold exposure memory in the absence of H3K36me3. During embryo development,VRN1 was silenced with the removal of active histone modifications in both winter and spring wheat, with selective restoration of H3K27me3 in winter wheat. The mutant of Tafie-cr-87, a component of H3K27me3 “writer” complex, did not influence the silence of VRN1during embryo development, but rather attenuated the cold exposure requirement of winter wheat. Integrating gene expression with H3K27me3 and H3K36me3 patterns identified potential regulators of flowering. This study unveils distinct roles of H3K27me3 and H3K36me3 in controlling vernalization response, maintenance, and resetting in winter wheat.

关键词： vernalization H3K27me3 H3K36me3 winter wheat resetting maintenance

同方期刊数据库

Implications of the Stellar Mass Density of High-z Massive Galaxies from JWST on Warm Dark Matter

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第1期24卷 128-134页

作者： Hengjie Lin Yan Gong Bin Yue xuelei Chen National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Science Center for China Space Station Telescope National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Center for High Energy Physics Peking UniversityBeijing 100871China

A significant excess of the stellar mass density at high redshift has been discovered from the early data release of James Webb Space Telescope(JWST),and it may require a high star formation ***,this will lead to large number density of ionizing photons in the epoch of reionization(EoR),so that the reionization history will be changed,which can arise tension with the current EoR *** dark matter(WDM),via the free streaming effect,can suppress the formation of small-scale structure as well as low-mass *** provides an effective way to decrease the ionizing photons when considering a large star formation efficiency in high-z massive galaxies without altering the cosmic reionization *** the other hand,the constraints on the properties of WDM can be derived from the JWST *** this work,we study WDM as a possible solution to reconcile the JWST stellar mass density of high-z massive galaxies and reionization *** find that,the JWST high-z comoving cumulative stellar mass density alone has no significant preference for either CDM or WDM *** using the observational data of other stellar mass density measurements and reionization history,we obtain that the WDM particle mass with mw=0.51_(-0.12)^(+0.22) keV and star formation efficiency parameter f_(*)^(0)> 0.39 in 2σ confidence level can match both the JWST high-z comoving cumulative stellar mass density and the reionization history.

关键词： Cosmology (cosmology:)dark matter (cosmology:)large-scale structure of universe

Progress of gaseous arsenic removal from flue gas by adsorption:Experimental and theoretical calculations

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第2期136卷 470-485页

作者： xuelei Yan Qingzhu Li Xiaowei Huang Bensheng Li Shengtu Li Qingwei Wang School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution Central South UniversityChangsha 410083China National Engineering Research Center for Rare Earth Materials General Research Institute for Non-Ferrous MetalsBeijing 100088China

Because of its high mobility and difficult capture,gaseous arsenic pollution control has become the focus of arsenic pollution *** mainly exists in the form of highly toxic As_(2)O_(3)in the flue ***,removing gaseous As_(2)O_(3)from flue gas is of great practical significance for arsenic pollution *** gaseous As_(2)O_(3)on the surface of adsorbents by physical or chemical adsorption is an effective way to reduce the content of arsenic in the flue gas and alleviate arsenic *** the past few decades,various adsorbents have been developed to capture gaseous As_(2)O_(3)in the flue gas,and their adsorption mechanisms have been studied in ***,it is necessary to review the strategies of arsenic removal from flue gas by adsorption,which can inspire further *** on summarizing the morphological distribution of gaseous As_(2)O_(3)in the flue gas,this review further summarizes the removal of gaseous As_(2)O_(3)by several adsorbents and the effect of temperature and the main components of the flue gas on arsenic *** addition,the mechanism of arsenic removal based on adsorption in the flue gas is discussed in depth through theoretical calculations,which is the particular focus of this ***,prospects based on the present research state of arsenic removal by adsorption are proposed to provide ideas for developing effective and stable adsorbents for arsenic removal from flue gas.

关键词： Gaseous arsenic Flue gas Adsorption Theoretical calculation Mechanism

Single droplet formation by controlling the viscoelasticity of polymer solutions during inkjet printing

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第6期35卷 244-248页

作者： Dong Lv xuelei Liu Wei Li Qiang Zhang Xinhong Yu Yanchun Han State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Inkjet printing has emerged as a potential solution processing method for large-area patterned *** inkjet printing,a single droplet without satellite droplet is required for high-quality ***,we propose a strategy for obtaining a single droplet by adjusting the reduced concentration(c/c^(*),where c^(*)is the critical overlap concentration)in the range of *** formation can be categorized into three distinct regimes:(1)c/c^(*)2.0,no ***,an inertial-capillary balance led to the 2/3-power scaling of the minimum radius with time for the solutions of c/c^(*)<***,for the solutions of c/c^(*)=1.0-1.5,the ligament radius decreased exponentially with ***,the Weissenberg number was higher than the critical value of 0.5,indicating that the polymer chains underwent coil-stretch *** viscoelastic-capillary balance dominated instead of the inertial-capillary *** resulting viscoelastic resistance reduced the length of the ligament and increased the velocity difference between the satellite and main ***,a single droplet was *** addition,the law can be successfully generalized to various molecular weights,molecular structures and solvents.

关键词： Inkjet printing Single droplet Satellite droplet Viscoelasticity Coil-stretch

The FRB-searching Pipeline of the Tianlai Cylinder Pathfinder Array

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第8期24卷 113-132页

作者： Zijie Yu Furen deng Shijie Sun Chenhui Niu Jixia Li Fengquan Wu Wei-Yang Wang Yougang Wang Shifan Zuo Lin Shu Jie Hao Xiaohui Liu Reza Ansari Ue-Li Pen Albert Stebbins Peter Timbie xuelei Chen National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy and Technology Chinese Academy of ScienceBeijing 100101China Institute of Astrophysics Central China Normal UniversityWuhan 430079China Institute of Automation Chinese Academy of SciencesBeijing 100190China Guangdong Institute of Artificial Intelligence and Advanced Computing Guangzhou 510535China UniversitéParis-Saclay CNRS/IN2P3IJCLab91405 OrsayFrance Institute of Astronomy and Astrophysics Academia SinicaRoosevelt RoadTaipei 10617TaiwanChina Canadian Institute for Theoretical Astrophysics University of Toronto60 Saint George StreetTorontoON M5S 3H8Canada Department of Physics University of Wisconsin-MadisonMadisonWI 53706USA Fermi National Accelerator Laboratory P.O.Box 500Batavia IL 60510-5011USA Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Center of High Energy Physics Peking UniversityBeijing 100871China

This paper presents the design,calibration,and survey strategy of the Fast Radio Burst(FRB)digital backend and its real-time data processing pipeline employed in the Tianlai Cylinder Pathfinder *** array,consisting of three parallel cylindrical reflectors and equipped with 96 dual-polarization feeds,is a radio interferometer array designed for conducting drift scans of the northern celestial *** FRB digital backend enables the formation of 96 digital beams,effectively covering an area of approximately 40 square degrees with the 3 dB *** pipeline demonstrates the capability to conduct an automatic search of FRBs,detecting at quasi-realtime and classifying FRB candidates *** current FRB searching pipeline has an overall recall rate of88%.During the commissioning phase,we successfully detected signals emitted by four well-known pulsars:PSR B0329+54,B2021+51,B0823+26,and B2020+*** report the first discovery of an FRB by our array,designated as FRB *** also investigate the optimal arrangement for the digitally formed beams to achieve maximum detection rate by numerical simulation.

关键词： instrumentation interferometers-methods data analysis-(stars )pulsars general-telescopes

中国公众参与可持续发展的现状分析与推进措施

在线全文

学校读者我要写书评

暂无评论

湖北社会科学 2005年第3期 37-39页

作者：邓学雷华中师范大学城市与环境科学学院湖北武汉430060

公众参与可持续发展对于实现可持续发展目标有着重要的意义。目前,有中国特色的公众参与正在逐步形成,体现在政策、法规、机制逐渐完善,宣传教育有所增强,公众参与意识有所提高等方面。但是中国目前仍然存在总体的参与意识还不高,参与... 详细信息

公众参与可持续发展对于实现可持续发展目标有着重要的意义。目前,有中国特色的公众参与正在逐步形成,体现在政策、法规、机制逐渐完善,宣传教育有所增强,公众参与意识有所提高等方面。但是中国目前仍然存在总体的参与意识还不高,参与水平参差不齐;公众参与可持续发展的政治与法律保障机制作用还不够;信息公开不够,公众参与成本高等制约公众参与可持续发展的因素。

关键词：公众参与可持续发展现状分析推进措施

A review on the transformation of birnessite in the environment:Implication for the stabilization of heavy metals

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第5期139卷 496-515页

作者： Miao Shi Qingzhu Li Qingwei Wang xuelei Yan Bensheng Li Linhai Feng Chao Wu Rongrong Qiu Hongkai Zhang Zhihui Yang Weichun Yang Qi Liao Liyuan Chai School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment ofHeavy Metal Pollution Central South UniversityChangsha 410083China Water Pollution Control Technology Key Lab of Hunan Province Changsha 410083China

Birnessite is ubiquitous in the natural environment where heavy metals are retained and easily *** surface properties and structure of birnessite change with the changes in external environmental conditions,which also affects the fate of heavy *** the effect and mechanism of the birnessite phase transition process on heavy metals is the key to taking effective measures to prevent and control heavy metal ***,the four transformation pathways of birnessite are summarized first in this ***,the relationship between transformation pathways and environmental conditions is *** relevant environmental conditions include abiotic(e.g.,co-existing ions,pH,oxygen pressure,temperature,electric field,light,aging,pressure)and biotic factors(e.g.,microorganisms,biomolecules).The phase transformation is achieved by the key intermediate of Mn(Ⅲ)through interlayer-condensation,folding,neutralizationdisproportionation,and dissolution-recrystallization *** AOS(average oxidation state)of Mn and interlayer spacing are closely correlated with the phase transformation of *** but not least,the mechanisms of heavy metals immobilization in the transformation process of birnessite are summed *** involve isomorphous substitution,redox,complexation,hydration/dehydration,*** transformation of birnessite and its implication on heavy metals will be helpful for understanding and predicting the behavior of heavy metals and the crucial phase of manganese oxides/hydroxides in natural and engineered environments.

关键词： Birnessite Transformation Heavy metals Pathways Mechanism

E-Cervix imaging displaying cervical elasticity characteristics of healthy adult nulliparous women at different age groups and different menstrual cycle stages

在线全文

学校读者我要写书评

暂无评论

中国医学影像技术 2024年第8期40卷 1208-1211页

作者： XU Yunyan WANG Mingli LYU Xiaoli LI xuelei Department of Ultrasound Anhui Women and Children's Medical CenterHefei 230001China The Fifth Clinical College of Anhui Medical University Hefei 230000China

Objective To observe the cervical elasticity of healthy adult nulliparous women at different age groups and different stages of menstrual cycle with E-Cervix imaging *** A total of 218 healthy adult nulliparous women who underwent transvaginal ultrasound examination for routine physical examination were retrospectively enrolled,including 103 in follicular phase,78 in ovulation phase and 37 in luteal *** canal length(CL)and E-Cervix elasticity parameters were compared among different age groups and different stages of menstrual cycle,including elasticity contrast index(ECI),hardness ratio(HR),cervical internal and external orifice strain values(IOS and EOS)and IOS/EOS *** No significant difference of CL nor cervical elasticity parameters was detected among healthy adult nulliparous women at different age groups(all P>0.05).There were significant differences of ECI,HR and IOS among different menstrual cycle stages(all P<0.05),among which women in follicular phase had higher ECI and IOS but lower HR than those in luteal phase(all P<0.05).Conclusion No significant difference of cervical elasticity existed among healthy adult nulliparous women at different age ***,cervical elasticity of healthy adult nulliparous women changed during menstrual cycle,in follicular phase had higher ECI and IOS but lower HR than in luteal phase.

关键词： cervix uteri menstruation ultrasonography elasticity imaging techniques