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Molecular self-induced configuration for improving dissymmetry factors in tetradentate platinum(Ⅱ) enantiomers cycloaddition

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Chinese Chemical Letters 2022年第3期33卷 1459-1462页

作者： Li yuan Qian-Jun Ding Zhen-Long tu Xiang-ji Liao Xu-Feng Luo Zhi-Ping Yan Zheng-Guang Wu You-Xuan Zheng State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Nantong Key Lab of Intelligent and New Energy Materials College of Chemistry and Chemical EngineeringNantong UniversityNantong 226019China

Two pairs of Pt(Ⅱ) enantiomers((RR)/(SS)-Py Pt,((RR)/(SS)-Py: N,N’-(1,2-diphenylethane-1,2-diyl)dipicolinamide;(RR)-P/M-QPt,((RR)/(SS)-Q: N,N’-((1R,2R)-1,2-diphenylethane-1,2-diyl)bis(quinoline-2-carboxamide)) were synthesized, respectively, with good circularly polarized luminescence(CPL) and tunable dissymmetry factors(g) by molecular self-induction with(RR)/(SS)-1,2-diphenylethane-1,2-diamine as carbon chiral sources. In the(RR)-P-QPt and(SS)-M-QPt, specific P-and M-configurations were effectively induced from intrinsic chiral carbon centres(R or S), ingeniously avoiding the racemic mixture formation and chiral separation. Furthermore, the chirality originating from both chiral carbon centres and helicene-like structure improves the g factor significantly, which provides a new molecular design strategy for chiral Pt(II) enantiomers with good CPL properties.

关键词： Pt(Ⅱ)enantiomer Circularly polarized luminescence Dissymmetry factor Molecular self-induction Helicene-like structure

Comparative assessment and analysis of Rortex vortex in swirling jets

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Journal of Hydrodynamics 2019年第3期31卷 495-503页

作者： Nan Gui Liang Ge Peng-xin Cheng Xing-tuan Yang Ji-yuan tu Sheng-yao jiang Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University Beijing 100084 China School of Engineering RMIT University Melbourne VIC 3083 Australia

Recently, a new definition, called Rortex, was proposed to quantify the purely rotational motion of fluids. In this work, based on the DNS data, the Rortex is used to assess and visualize the rotational motion and structure of the vortex in swirling jets in comparison with other kinds of vortex criteria, including Q , λ2,vorticity and Ω criteria. The Rortex vector,Ω, Q and criteria are found to be better than the vorticity criterion for the vortex core identification. The vector triangle formed by the Rortex R , the nonrotational shear S , and the vorticity R is analyzed to give mechanical explanations, especially of the effect of the non-rotational shear on the rotation of fluids. In addition, the probability density distributions (PDF) of the Rortex R , the nonrotational shear S, and the vorticity R are computed. The peak value of the PDF of the vorticity could be used to explain the pure rigid rotation effect and the combination effects of the rigid rotation and the non?rotational shear.

关键词： Swirling flow vortex Rortex direct numerical simulation rigid rotation non-rotational shear

A review of paleoenvironmental reconstruction using crater lake sediments in monsoonal China

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Journal of Earth Science 2022年

作者： Xuanqiao Liu Shiwei jiang Luyao tu Dorcas B.Oyebanji Xiaoyan Liu Yufeng yuan Xiangzhong Li Ming ji Guangcheng Zhang Xin Zhou College of Marine Science and Engineering， Nanjing Normal University Yunnan Key Laboratory of Earth System Science， Yunnan University School of Earth and Space Science， University of Science and Technology of China School of Chemistry， Biology and Environment， Yuxi Normal University Anhui Geological Archives

The sediments of crater lakes were one of the ideal archives for high-resolution paleoenvironmental reconstruction. This paper collected sedimentary records of 21 crater lakes in monsoonal China and systematically discussed the geographical distribution and formation ages of these crater lakes. Sediment provenance of crater lakes and its influencing factors were analyzed， and paleoenvironmental sequences and human activities records on different timescales reconstructed by crater lake sediments in monsoonal China were reviewed. The following points are highlighted: (1) Crater lakes in monsoonal China have been shown to preserve continuous long-time sediments that can exceed even 400 kyr， although the chronology of some sediments in southern China is debated and there were currently fewer long time records from northeastern China; (2) The sediment provenance of crater lakes in northern China (e.g. aeolian inputs) was different from that in southern China (e.g. the volcanic-lake rim)， due to the different location and deposition conditions of crater lakes; (3) Crater lake sediments have been used to reconstruct the history of climate changes on different timescales， but reconstruction studies of glacial-interglacial and decadal-annual scale records and studies of spatial comparisons of records on different timescales still need to be strengthened; (4) The anthropogenic signals， which include cultivation， logging， and industrial activity， are well documented in crater lake sediments from different areas and can therefore provide key evidence for the study of the Anthropocene. Crater lake sediments are vital paleoclimate archives for the reconstruction of high-resolution climate changes and for the understanding of the impact of anthropogenic activities. However， there are still questions that need to be solved， and a more comprehensive study of crater lake sediments is expected in the future.

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Predictive parameters on CT scan for dysthyroid optic neuropathy

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International Journal of Ophthalmology(English edition) 2020年第8期13卷 1266-1271页

作者： Bo Yu Can Gong yuan-Fei ji Yu Xia Yun-Hai tu Wen-Can Wu Department of Orbital and Oculoplastic Surgery Eye Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina Department of Ophthalmology Loudi Central HospitalLoudi 417000Hunan ProvinceChina Eye Hospital of Wenzhou Medical University Wenzhou 325000ZhejiangProvinceChina

AIM:To evaluate the value of parameters on CT scan in predicting dysthyroid optic neuropathy(DON)and to provide guidance for early diagnosis of DON accordingly.METHODS:A total of 67 eyes of 35 patients with thyroid-associated ophthalmopathy(TAO)were included in this study.Patients were divided into 2 groups(DON group and non-DON group).Parameters were measured on high resolution CT,including muscle index(MI),superior ophthalmic vein(SOV)dilatation,extraocular muscle volume/orbit volume(MV/OV),and intracranial fat prolapsed,and be compared between these 2 groups.The relation between those parameters and visual function[visual acuity(VA)and visual field defect(VF defect)]were also evaluated.RESULTS:MI and MV/OV were significantly higher in DON group(P=0.00035 and P=0.00026).No significant difference was detected regarding intracranial fat prolapse existence and SOV dilatation(P=0.37 and P=0.15).MV/OV was found to have significant negative correlation with both VF defect(R=-0.332,P=0.0273)and VA(R=-0.635,P=0.00)while MI was found to have negative linear correlation with VA only(R=-0.456,P=0.00017).The area under receiver operating characteristic curves was 0.82 for MV/OV and 0.75 for MI.The best performance in detecting DON was achieved when MV/OV is set at 0.20 with 72%sensitivity and 87%specificity and MI is set at 0.52 with 64%sensitivity and 80%specificity.CONCLUSION:MI and MV/OV are predictive parameters for DON.Together with clinical manifestations,MV/OV≥0.2 can be used as a good indicator for DON in TAO patients.

关键词： dysthyroid optic neuropathy muscle index superior ophthalmic vein dilatation intracranial fat prolapse muscle volume/orbital volume

Analysis and correlation of fluid acceleration with vorticity and Liutex(Rortex)in swirling jets

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Journal of Hydrodynamics 2019年第5期31卷 864-872页

作者： Nan Gui Hou-bo Qi Liang Ge Peng-Xin Cheng Hao Wu Xing-tuan Yang Ji-yuan tu Sheng-yao jiang Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing100084China School of Engineering RMIT UniversityMelbourneAustralia

The characteristics of the acceleration a and its correlation with the vortex core in the swirling flow are analyzed in this paper.The swirling flows of four swirl numbers(Sn=n S 0,0.10,0.20 and 0.36)are simulated by the direct numerical simulation,and the fluid mass particles from the inlet of the swirling flow are traced as a database for the current study.The correlations of the acceleration a with the vortex identification parameters of R andωare quantified,where R is the parameter of the“Liutex”-method proposed by Prof.Liu,and its early version is“Rortex”.The probability density functions of the included angles of a-R and a-ωare computed,which are used to clarify the geometrical configuration between a and R.The covariance coefficients between a and the parameters of various vortex core criteria(Q,λ2,ΩL,ΩR,ωand R)are computed and their relative levels of correlation are compared.Compared to the velocity,the expectation and the rms of the acceleration magnitudes and its projections on R and the plane perpendicular to R are computed for better explaining the correlation features between a and R.It is found that a and R are always either perpendicular or parallel to each other with the quantized included angles of∠(a,R)=kπ/2,(k=0,1,2).This confirms the role of R which works as the axis of the vortex exclusively.

关键词： swirling flow acceleration correlation vortex Rortex Liutex direct numerical simulation

Hepatic protective effects of Shenling Baizhu powder, a herbal compound, against inflammatory damage via TLR4/NLRP3 signalling pathway in rats with nonalcoholic fatty liver disease

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Journal of Integrative Medicine 2021年第5期19卷 428-438页

作者： Mao-xing Pan Chui-yang Zheng yuan-jun Deng Kai-rui Tang Huan Nie ji-qian Xie Dong-dong Liu Gui-fang tu Qin-he Yang Yu-pei Zhang School of Traditional Chinese Medicine Jinan UniversityGuangzhou 510632Guangdong ProvinceChina

Objective: High-fat diet(HFD) and inflammation are two key contributors to nonalcoholic fatty liver disease(NAFLD). Shenling Baizhu powder(SLBZP), a classical herbal compound, has been successfully used to alleviate NAFLD. However, its specific mechanisms are not fully understood. In this study, we assessed the anti-NAFLD effect of SLBZP in vivo.Methods: Rats were fed an HFD with or without SLBZP or with probiotics. At the end of week 16, an echo magnetic resonance imaging(EchoMRI) body composition analyser was used to quantitatively analyse body composition;a micro-computed tomography(micro-CT) imaging system was used to evaluate whole body and liver fat;and the Moor full-field laser perfusion imager 2 was used to assess liver microcirculation, after which, all rats were sacrificed. Then, biochemical indicators in the blood and the ultrastructure of rat livers were evaluated. Protein expression related to the liver Toll-like receptor 4(TLR4)/Nod-like receptor family pyrin domain-containing 3(NLRP3) signalling pathway was assessed using Western blot analysis. Further, high-throughput screening of 29 related inflammatory factors in liver tissue was performed using a cytokine array.Results: SLBZP supplementation reduced body weight, serum free fatty acid, and insulin resistance index(Ptural abnormalities. EchoMRI and micro-CT quantitative analyses showed that treatment with SLBZP reduced fat mass and visceral fat(P<0.05 and P<0.01, respectively). In addition, SLBZP decreased the expression of lipopolysaccharide(LPS)-activated TLR4/NLRP3 signalling pathway-related proteins and altered the expression levels of some inflammatory cytokines in liver tissues.Conclusion: SLBZP can inhibit NLRP3 inflammasome activation and interleukin-1 b release by suppressing LPS-induced TLR4 expression in rats with HFD-induced NAFLD. Thus, SLBZP may be beneficial for the prevention and treatment of inflammatory damage and associated diseases.

关键词： Nonalcoholic fatty liver disease Shenling Baizhu powder Traditional Chinese medicine TLR4/NLRP3 signalling pathway

科学与艺术的结合:一位科学家的独特见解——学习《钱学森书信》体会之二

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西安交通大学学报（社会科学版） 2009年第2期29卷 35-39页

作者：涂元季中国人民解放军总装备部北京100034

钱学森认为科学与艺术是结合的,技术和艺术是伴生的。他提出科技工作者要有一点文学素养,文学艺术家也要懂一些科学技术。科学与艺术的结合都不是简单的结合,而是文理相通、辩证统一的。钱老本人就是一个成功的典范,他是一位科学家,但... 详细信息

钱学森认为科学与艺术是结合的,技术和艺术是伴生的。他提出科技工作者要有一点文学素养,文学艺术家也要懂一些科学技术。科学与艺术的结合都不是简单的结合,而是文理相通、辩证统一的。钱老本人就是一个成功的典范,他是一位科学家,但在文学艺术方面有很高的素养,对书画、文学作品、音乐等方面都有深刻的见解。

关键词：钱学森科学艺术

Thiol-acrylate Catalyst Enabled Post-Synthesis Fabrication of Liquid Crystal Actuators

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高分子科学:英文版 2023年第10期41卷 1656-1662页

作者： Huan Liang Ya-Wen Liu Hong-tu Xu Yang Yang En-jian He Zhijun Yang Yen Wei Yan ji K The Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing100084China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China Department of Chemistry Center for Nanotechnology and Institute of Biomedical TechnologyChung-Yuan Christian UniversityTaiwan32023China

Synthesizing orientated liquid crystal elastomers(LCEs)via the two-stage thiol-acrylate Michael addition and photopolymerization(TAMAP)reaction is extensively used.However,excess acrylates,initiators,and strong stimuli are inevitably involved in the second stage crosslinking.Herein,we simplify the strategy through taking advantage of a volatile alkaline(originally added to catalyze the thiol-acrylate addition in the first crosslinking stage).Without excess functional groups,the residual catalyst after annealing is still enough to trigger reactions of dynamic covalent bonds at a relatively mild temperature(80℃)to program the alignment of LCEs.The reversible reaction switches off by itself after this process since the catalyst gradually but totally evaporates upon heating.The obtained soft actuators exhibit robust actuation during repeated deformation(over 1000 times).Many shape-morphing modes can be achieved by rationally designing orientation patterns.This strategy not only facilitates the practical synthesis of LCE actuators,but also balances the intrinsic conflict between stability and reprogrammability of exchangeable LCEs.Moreover,the method of applying volatile catalysts has the potential to be extended to other dynamic covalent bonds(DCBs)applied to crosslinked polymer systems.

关键词： Liquid crystal elastomer Vitrimer Covalent adaptable network Soft actuator

从系统科学角度认识理解和贯彻落实科学发展观——钱学森学习体会

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西安交通大学学报（社会科学版） 2008年第5期28卷 52-56页

作者：涂元季中国人民解放军总装备部北京100034

以钱学森为代表的中国学派的系统科学总的学术观点是辩证唯物主义的,与科学发展观所蕴含的社会和谐及统筹兼顾的思想观点完全一致。钱学森先生认为科学发展观是以胡锦涛为总书记的党中央关于社会发展问题的一个重大理论创新。在贯彻落... 详细信息

以钱学森为代表的中国学派的系统科学总的学术观点是辩证唯物主义的,与科学发展观所蕴含的社会和谐及统筹兼顾的思想观点完全一致。钱学森先生认为科学发展观是以胡锦涛为总书记的党中央关于社会发展问题的一个重大理论创新。在贯彻落实科学发展观的过程中各级领导干部学点系统科学知识,懂点综合集成方法,有助于从总体上把握并解决问题,使我们的工作多一点科学性和预见性,少一点片面性和盲目性。对复杂系统中出现的突发的"涌现",社会主义中国是有办法应对和解决的,这也充分体现了社会主义制度的优越性。

关键词：钱学森系统科学科学发展观