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Highly Flexible and Broad‑Range Mechanically Tunable All‑Wood Hydrogels with Nanoscale Channels via the Hofmeister Effect for Human Motion Monitoring

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Nano-Micro Letters 2022年第5期14卷 192-205页

作者： Guihua Yan Shuaiming He Gaofeng Chen Sen Ma anqi zeng Binglin Chen Shuliang Yang Xing Tang Yong Sun Feng Xu Lu Lin Xianhai zeng College of Energy Xiamen UniversityXiamen 361102People’s Republic of China State Key Laboratory of Pulp and Paper‑Making Engineering South China University of TechnologyGuangzhou 510640People’s Republic of China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityNo.35Tsinghua East RoadHaidianBeijing 100083People’s Republic of China

Wood-based hydrogel with a unique anisotropic structure is an attractive soft material,but the presence of rigid crystalline cellulose in natural wood makes the hydrogel less *** this study,an all-wood hydrogel was constructed by cross-linking cellulose fibers,polyvinyl alcohol(PVA)chains,and lignin molecules through the Hofmeister *** all-wood hydrogel shows a high tensile strength of 36.5 MPa and a strain up to~438%in the longitudinal direction,which is much higher than its tensile strength(~2.6 MPa)and strain(~198%)in the radial direction,*** high mechanical strength of all-wood hydrogels is mainly attributed to the strong hydrogen bonding,physical entanglement,and van der Waals forces between lignin molecules,cellulose nanofibers,and PVA *** to its excellent flexibility,good conductivity,and sensitivity,the all-wood hydrogel can accurately distinguish diverse macroscale or subtle human movements,including finger flexion,pulse,and swallowing *** particular,when“An Qi”was called four times within 15 s,two variations of the pronunciation could be *** recyclable,biodegradable,and adjustable mechanical properties,the all-wood hydrogel is a multifunctional soft material with promising applications,such as human motion monitoring,tissue engineering,and robotics materials.

关键词： Wood hydrogel Hofmeister effect Tunable mechanical strength Flexible Biodegradable

NiAl催化剂催化5-羟甲基糠醛加氢制备2,5-二羟甲基四氢呋喃

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厦门大学学报（自然科学版） 2024年第1期63卷 82-93页

作者：曾安琪闫贵花孙勇曾宪海林鹿唐兴厦门大学能源学院福建省生物质清洁高值化技术工程研究中心厦门市生物质清洁高值化利用重点实验室福建厦门361005

[目的] 5-羟甲基糠醛(HMF)是最重要的生物质基平台化学品之一,可以通过催化加氢途径制备许多高附加值化学品.本文为设计在更加温和的条件下达到高效催化HMF加氢的非贵金属催化剂进行了一系列研究.[方法]通过尿素共沉淀法制备了一种NiAl... 详细信息

[目的] 5-羟甲基糠醛(HMF)是最重要的生物质基平台化学品之一,可以通过催化加氢途径制备许多高附加值化学品.本文为设计在更加温和的条件下达到高效催化HMF加氢的非贵金属催化剂进行了一系列研究.[方法]通过尿素共沉淀法制备了一种NiAl催化剂,考察了NiAl催化剂催化HMF加氢制备2,5-二羟甲基四氢呋喃(BHMTHF)的性能,并利用X射线衍射(XRD)、氢气程序升温还原(H_(2)-TPR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、氨气程序升温脱附(NH_(3)-TPD)、X射线光电子能谱(XPS)等表征方法系统地研究了不同Ni/Al比、不同煅烧温度和还原温度对催化剂理化性质的影响.[结果] Ni和Al的投料原子比为3∶1,在350℃下煅烧、650℃下还原制备的催化剂Ni_(3)Al-350-650在100℃、氢气压力2.5 MPa的条件下反应1 h,HMF的转化率和BHMTHF产率分别高达99.5%和87.5%.过高的Ni/Al比制备的催化剂比表面积较小,导致暴露的活性位点较少从而降低了催化活性,通过煅烧温度可以调节NiAl催化剂的可还原性.[结论]本研究实现了在温和条件下HMF的高效催化加氢转化.该结果可为用于HMF定向转化的非贵金属催化剂的设计提供参考.

关键词：生物质还原氢化 5-羟甲基糠醛非贵金属 2,5-二羟甲基四氢呋喃

Aureobasidium subglaciale F134 is a bifunctional whole-cell biocatalyst for Baeyer-Villiger oxidation or selective carbonyl reduction controllable by temperature

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Chinese Journal of Chemical Engineering 2020年第12期28卷 3044-3051页

作者： Liqun Shen Ran Cang Guang Yang anqi zeng He Huang Zhigang Zhang School of Pharmaceutical Sciences Nanjing Tech UniversityNanjing 211816China State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech UniversityNanjing 211816China

The microbial production of either ester/lactones or enantio-enriched alcohols through Baeyer-Villiger oxidation or stereoselective reduction of ketones,respectively,is possible by using whole cells of *** F134 as a bifunctional *** chemoselective pattern of acetophenone biotransformation catalyzed by these cells can be regulated through reaction temperature,directing the reaction either towards oxidation or reduction *** Baeyer–Villiger oxidation activity of *** F134 whole cells is particularly dependent on reaction *** was transformed efficiently to phenol via the primary Baeyer–Villiger product phenyl acetate at 20℃ after 48 h with 100% *** contrast,at 35℃,enantio-enriched(S)-1-phenylethanol was obtained as the sole product with 64% conversion and 89% *** addition,*** F134 cells also catalyze the selective reduction of various structurally different aldehydes and ketones to alcohols with 40% to 100% yield,indicating broad substrate spectrum and good enantioselectivity in relevant *** study provides a bifunctional biocatalyst systemthat can be used in Baeyer–Villiger oxidation aswell as in asymmetric carbonyl reduction,setting the stage for future work concerning the identification and isolation of the respective enzymes.

关键词： Biocatalysis Whole cells Baeyer-Villiger oxidation Aureobasidium subglaciale Carbonyl reduction

Comparative Study on Different Methods for Prediction of Thermal Insulation Performance of Thermal Barrier Coating Used on Turbine Blades

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Journal of Thermal Science 2024年第1期33卷 172-189页

作者： ZHANG Zhixin zeng Wu ZHANG Xiaodong zeng Yuntao Advanced Gas Turbine Laboratory Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Advanced Energy and Power Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Innovation Academy for Light-duty Gas Turbine Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

As turbine inlet temperature gets higher and higher,thermal barrier coating(TBC) is more and more widely used in turbine *** turbine blades with TBC,it is of great significance to evaluate the temperature distribution of its substrate metal quickly and accurately,especially during the design *** different degrees of simplification such as whether to consider the change of the geometric size of the fluid domain by TBC and whether to consider the planar heat conduction in TBC,three different methods used in conjugate heat transfer(CHT) simulation to model the TBC of the turbine blades have been developed and widely used by ***,little research has been conducted to investigate the influence of the three methods on the temperature distribution of turbine *** fill this gap,three geometric models were *** are a solid conduction model with a substrate metal layer and a TBC layer,a transonic turbine vane with internal cooling and TBC,and a plate cylindrical film hole cooling model with *** methods were used in these geometric models and their differences were carefully analyzed and *** result shows that for the conduction model used in this paper,with the same TBC surface temperature distribution,the difference between the three methods is very small and can be *** a transonic turbine vane with internal cooling,regarding the local maximum temperature of the substrate-TBC interface,the largest difference between the method in which TBC is considered as a thermal resistance or a virtual layer of cells and the method in which three-dimensional heat conduction equation of TBC is solved occurs at the trailing *** difference near the leading edge is below *** employed to the film cooling model,the difference of the laterally averaged temperature of the substrate-TBC interface can be 8 K which is mainly due to the change of the length to diameter ratio of the film cooling hole by *** the substrate

关键词： turbine blade thermal barrier coating conjugate heat transfer film cooling hole

Nested Saturated Control of Uncertain Complex Cascade Systems Using Mixed Saturation Levels

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1163-1174页

作者： Meng Li Zhigang zeng Wuhan National Laboratory for Optoelectronics Wuhan 430074 School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 Key Laboratory of Image Processing and Intelligent Control of Education Ministry of China Wuhan 430074China

This study addresses the problem of global asymptotic stability for uncertain complex cascade systems composed of multiple integrator systems and non-strict feedforward nonlinear systems. To tackle the complexity inherent in such structures, a novel nested saturated control design is proposed that incorporates both constant saturation levels and state-dependent saturation levels. Specifically, a modified differentiable saturation function is proposed to facilitate the saturation reduction analysis of the uncertain complex cascade systems under the presence of mixed saturation levels. In addition, the design of modified differentiable saturation function will help to construct a hierarchical global convergence strategy to improve the robustness of control design scheme. Through calculation of relevant inequalities, time derivative of boundary surface and simple Lyapunov function,saturation reduction analysis and convergence analysis are carried out, and then a set of explicit parameter conditions are provided to ensure global asymptotic stability in the closed-loop systems. Finally, a simplified system of the mechanical model is presented to validate the effectiveness of the proposed method.

关键词： method saturation differentiable

Aggregation-regulated bioreduction process of graphene oxide by Shewanella bacteria

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Chinese Journal of Chemical Engineering 2024年第5期69卷 56-62页

作者： Kaixin Han Yibo zeng Yinghua Lu Ping zeng Liang Shen Department of Chemical and Biochemical Engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China Chinese Research Academy of Environmental Sciences Beijing 100012China

The bioreduction of graphene oxide(GO)using environmentally functional bacteria such as Shewanella represents a green approach to produce reduced graphene oxide(rGO).This process differs from the chemical reduction that involves instantaneous molecular *** bioreduction,the contact of bacterial cells and GO is considered the rate-limiting *** reveal how the bacteria-GO integration regulates rGO production,the comparative experiments of GO and three Shewanella strains were carried ***-transform infrared spectroscopy,X-ray photoelectron spectroscopy,Raman spectroscopy,and atomic force microscopy were used to characterize the reduction degree and the aggregation *** results showed that a spontaneous aggregation of GO and Shewanella into the condensed entity occurred within 36 h.A positive linear correlation was established,linking three indexes of the aggregation potential,the bacterial reduction ability,and the reduction degree(ID/IG)comprehensively.

关键词： Graphene oxide Reduced graphene oxide Bioreduction Aggregation Shewanella

Cluster analysis reveals a homogeneous subgroup of PCOS women with metabolic disturbance associated with adverse reproductive outcomes

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Chinese Medical Journal 2024年第5期137卷 604-612页

作者： Hanxiao Chen Rujun zeng Xun zeng Lang Qin The Reproductive Medical Center Department of Obstetrics and GynecologyWest China Second University HospitalSichuan UniversityChengduSichuan 610041China Key Laboratory of Birth Defects and Related of Women and Children of Ministry of Education West China Second University HospitalSichuan UniversityChengduSichuan 610041China

Background:Polycystic ovarian syndrome(PCOS)is a heterogeneous and complex reproductive endocrinological disease that could lead to *** were many attempts to classify PCOS but it remains unclear whether there is a specific subgroup of PCOS that is associated with the best or worst reproductive outcomes of assisted reproductive techniques(ART).Methods:Infertile PCOS patients who underwent their first cycle of in vitro fertilization(IVF)in West China Second University Hospital,Sichuan University from January 2019 to December 2021 were *** clinical and laboratory information of each individual were *** cluster analysis was *** ovarian stimulation parameters and reproductive outcomes were collected and compared between the different clusters of ***:Our analysis clustered women with PCOS into"reproductive","metabolic",and"balanced"clusters based on nine *** group was characterized by high levels of testosterone(T),sex hormone-binding globulin(SHBG),follicular stimulation hormone(FSH),luteinizing hormone(LH),and anti-Müllerian hormone(AMH).Metabolic group was characterized by high levels of body mass index(BMI),fasting insulin,and fasting *** group was characterized by low levels of the aforementioned reproductive and metabolic parameters,except for *** with PCOS patients in reproductive and balanced clusters,those in metabolic cluster had lower rates of good quality day 3 embryo and blastocyst ***,PCOS patients in the reproductive cluster had greater fresh embryo transfer(ET)cancelation rate and clinical pregnancy rate after fresh ET than metabolic cluster(odds ratio[OR]=3.37,95%confidence interval[CI]:1.77-6.44,and OR=6.19,95%CI:1.58-24.24,respectively).And compared with PCOS of metabolic cluster,PCOS of balanced cluster also had higher chance for fresh ET cancelation(OR=2.83,95%CI:1.26-6.35).Conclusion:Our study suggested that PCOS patients in met

关键词： Polycystic ovarian syndrome Assisted reproductive techniques Clustering analysis Metabolic disturbance Clinical pregnancy

清洁能源转型下关键金属产业链碳排放研究综述与展望

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资源科学 2023年第1期45卷 1-17页

作者：朱学红李双美曾安琪中南大学商学院长沙410083 中南大学金属资源战略研究院长沙410083 中南大学马克思主义学院长沙410083

【目的】在全球碳中和背景下,清洁能源技术迎来井喷期,关键金属需求及产业链碳排放将大幅攀升。【方法】为了深入厘清清洁能源转型下关键金属产业链碳排放的驱动机理、研究方法和减排路径,本文基于系统性关联视角,站在全产业链的高度对... 详细信息

【目的】在全球碳中和背景下,清洁能源技术迎来井喷期,关键金属需求及产业链碳排放将大幅攀升。【方法】为了深入厘清清洁能源转型下关键金属产业链碳排放的驱动机理、研究方法和减排路径,本文基于系统性关联视角,站在全产业链的高度对相关研究进行了系统梳理和整合分析。【结果】研究发现:(1)清洁能源转型从需求侧拉动关键金属需求,从供给侧降低碳排放强度,供需双轮共同驱动关键金属产业链碳排放;(2)关键金属产业链碳排放核算和预测需集成多种方法模型,应根据不同的分析对象选择适配的研究方法;(3)现有研究重点关注关键金属冶炼和回收环节的碳减排路径,尚未从全产业链的角度识别降碳路径。【结论】未来需基于“金属-能源-碳”多要素关联视角和集成性方法进一步验证关键金属产业链碳排放的内在机理并研判其未来态势,在此基础上结合“中国因素”系统性地设计和识别关键金属全产业链碳减排路径,为达成碳中和目标提供现实依据和决策参考。

关键词：清洁能源转型关键金属碳排放系统性关联视角全产业链

Analysis of gravity wave activity during stratospheric sudden warmings in the northern hemisphere

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Earth and Planetary Physics 2024年第2期8卷 415-422页

作者： XuanYun zeng Guang Zhong School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410000China Key Laboratory of Geospace Environment Chinese Academy of SciencesUniversity of Science&Technology of ChinaHefei 230026China

Due to the significant changes they bring to high latitude stratospheric temperature and wind,stratospheric sudden warmings(SSWs)can have an impact on the propagation and energy distribution of gravity waves(GWs).The variation characteristics of GWs during SSWs have always been an important *** temperature data from January to March in 2014−2016,provided by the Constellation Observing System for Meteorology,Ionosphere and Climate(COSMIC)mission,we have analyzed global GW activity at 15−40 km in the Northern Hemisphere during SSW *** the SSWs that we studied,the stratospheric temperature rose in one or two longitudinal regions in the Northern Hemisphere;the areas affected extended to the east of 90°*** these SSWs,the potential energy density(E_(p)of GWs expanded and covered a larger range of longitude and altitude,exhibiting an eastward and downward *** E_(p)usually increased,while partially filtered by the eastward zonal *** zonal winds weakened or turned westward,E_(p)began to *** SSWs,the E_(p)usually *** observations can serve as a reference for analyzing the interaction mechanism between SSWs and GWs in future work.

关键词： stratospheric sudden warming gravity wave wind filter