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Visible transparent,infrared stealthy polymeric films with nanocoating of ITO@MXene enable efficient passive radiative heating and solar/electric thermal conversion

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Nano Research 2023年第2期16卷 3326-3332页

作者： Xingyuan Du Xiangxin Li Yuxuan Zhang Xinyi Guo Zhengji Li Yanxia Cao Yanyu Yang Wanjie Wang Jianfeng wang College of Materials Science and Engineering Henan Key Laboratory of Advanced Nylon Materials and ApplicationZhengzhou UniversityZhengzhou 450001China China Construction Seventh Engineering Division Corp.Ltd. Zhengzhou 450004China

Visible transparent yet low infrared-emissivity(ε)polymeric materials are highly anticipated in many applications,whereas the fabrication of which remains a formidable challenge.Herein,visible transparent,flexible,and low-εpolymeric films were fabricated by nanocoating decoration of indium tin oxide(ITO)and MXene on polyethylene terephthalate(PET)film surface through magnetron sputtering and spray coating,respectively.The obtained PET-ITO@MXene(PET-IM)film exhibits lowεof 24.7%and high visible transmittance exceeding 50%,endowing it with excellent visible transparent infrared stealthy by reducing human skin radiation temperature from 32 to 20.8°C,and remarkable zero-energy passive radiative heating capability(5.7°C).Meanwhile,the transparent low-εPET-IM film has high solar absorptivity and electrical conductivity,enabling superior solar/electric to thermal conversion performance.Notably,the three heating modes of passive radiative and active solar/electric can be integrated together to cope with complex heating scenarios.These visible transparent low-εpolymeric films are highly promising in infrared stealth,building daylighting and thermal management,and personal precision heating.

关键词： transparent polymeric film nanocoating decoration ITO@MXene low infrared emissivity passive radiative heating solar/electric heating

Structural disruption of melanin-like polymers with boosted UV protection

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Science China Chemistry 2024年第5期67卷 1653-1663页

作者： Zhen Yang Xianheng wang wanjie Bai Zikun Zou Haoxing Wu Yiwen Li Department of Radiology Huaxi MR Research CenterFunctional and Molecular Imaging Key Laboratory of Sichuan ProvinceNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengdu 610041China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

Manipulating the energy structure of materials represents an efficient way to regulate their light absorption behaviors. For example, constructing donor-acceptor(D-A) structures to increase the polarizability and reduce the energy bandgap of local molecules has been widely used in the field of organic photovoltaics with ordered structures. Remarkably, even in disordered and chaotic systems such as melanin-like polydopamine(PDA), visible and near-infrared light absorption can be significantly improved using this strategy. However, there has been a noticeable dearth of research on the ultraviolet(UV) light absorption regulation of bioinspired polymers with disordered and chaotic architectures by tailoring the D-A microstructures. In this study, a series of benzoheterocyclic molecules with strong electron-donating features screened by molecular simulation calculations were involved in disrupting the D-A structures within PDA. The destruction of D-A structures promoted the increase of the energy band gap and finally boosted the UV absorption of PDA. The resulting PDA nanoparticles with enhanced UV absorption were further employed to fabricate UV shielding composite films to protect the growth of plants from harmful UV radiation. This research may open up new avenues for structural disruption of bioinspired polymers for enhanced photoprotection applications.

关键词： melanin-like polymers polydopamine D-A structure UV absorption photoprotection

Numerical Determination of the Circumferential Residual Stress of Porcine Aorta by Pulling-Back Method

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Acta Mechanica Solida Sinica 2021年第3期34卷 346-355页

作者： Heming Chen Wanjie Wang Qiang Chen Zhiyong Li School of Biological Science and Medical Engineering Southeast UniversityNanjing 210096China School of Mechanical Medical and Process EngineeringQueensland University of TechnologyBrisbaneQLD 4001Australia

Residual stress is very important for the study of cardiovascular-relevant issues,such as assessing the vulnerability of atherosclerosis and aneurysm.In this paper,the circumferential residual stress of porcine aorta was characterized by combining ex vivo experiments with numerical studies.In the experiments,porcine aortic rings were prepared and cut open,and the cross sections of the opened aortic rings were extracted to construct finite element models.The 5-parameter Mooney-Rivlin model was chosen to describe the tensile mechanical behavior of the aorta.In numerical studies,based on the finite element models and hyperelastic material model,a pulling-back displacement was applied to reclose the models of the opened aortic rings,and the equivalent circumferential residual stress to the pre-opened aorta was analyzed.The results showed that the circumferential residual stress of the aorta generally decreased from the proximal to the distal ends,and the residual stresses of the aortic rings close to the distal end did not show a great difference.This work provides an improved understanding of the residual stress distribution in aorta and may be used as a more realistic initial condition for future stress analysis of the arterial tissue.

关键词： Aorta Circumferential residual stress Opening angle Finite element model

Effects of drought on non-structural carbohydrates and C,N,and P stoichiometric characteristics of Pinus yunnanensis seedlings

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Journal of Forestry Research 2024年第1期35卷 90-102页

作者： Zhijuan Zhao Lina wang Yuanxi Liu Jianli Sun Jiandong Xiao Qiong Dong Lianfang Li wanjie Zhang Chao wang Junwen Wu College of Forestry Southwest Forestry UniversityKunming 650224YunnanPeople’s Republic of China

To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,light and moderate and severe drought treatments[(80±5),(65±5),(50±5),and(35±5)%of field water-holding capacity].Non-structural carbohydrates,carbon(C),nitrogen(N),and phosphorus(P)concentrations were measured in each plant component.The results show that:(1)With increasing drought,non-structural carbohydrates gradually increased in leaves,stems,and coarse roots,while gradually decreased in fine roots;(2)C concentrations of all were relatively stable under different stress levels.Phosphorous utilization of each component increased under light and moderate drought conditions,while N and P utilization efficiency of each plant component decreased under severe drought.Growth was mainly restricted by N,first decreasing and then increasing with increased drought;(3)There was a correlation between the levels of non-structural carbohydrates and C,N,and P in each component.Changes in N concentration affected the interconversion between soluble sugar and starch,which play a regulatory role in the fluctuation of the concentration of non-structural carbohydrates;and,(4)Plasticity analysis showed that P.yunnanensis seedlings responded to drought mainly by altering starch concentration,the ratio of soluble sugar to starch in leaves and stems,and further by alter-ing N and P utilization efficiencies.Overall,these results suggest that the physiological activities of all organs of P.yunnanensis seedlings are restricted under drought and that trade-offs exist between different physiological indicators and organs.Our findings are helpful in understanding non-structural carbohydrate and nutrient adaptation mechanisms under drought in P.yunnanensis seedlings.

关键词： Pinus yunnanensis seedlings Drought Non-structural carbohydrates C,N,P stoichiometric characteristics

Manipulating the antioxidative capacity of melanin-like nanoparticles by involving condensation polymerization

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Science China Chemistry 2023年第5期66卷 1520-1528页

作者： Peng Yang Tianyou wang Jianhua Zhang Hengjie Zhang wanjie Bai Gaigai Duan Wei Zhang Jinrong Wu Zhipeng Gu Yiwen Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China Laboratory for Biomaterials and Drug Delivery Department of AnesthesiologyCritical Care and Pain MedicineBoston Children’s HospitalHarvard Medical SchoolBostonMassachusetts 02115USA

Melanin is ubiquitous in nature and plays important roles in physiological activities especially in keeping the oxidative balance.Both natural and synthetic melanin were synthesized via the free radical polymerization of 5,6-dihydroxyindole(DHI)monomer,which may lead to the inherent compactπ-conjugation stacking microstructures and finally results in limited antioxidative capacities.To address this issue,we have strived to involve condensation polymerization during the melanin synthetic process,aiming to disrupt the compact stacking microstructures and improve the total antioxidative performance.The resulting melaninlike nanoparticles(NPs)indeed possessed less compact stackingπ-conjugation structures and decreased density,which further demonstrated enhanced antioxidative abilities compared with conventional melanin-like polymers such as poly-5,6-dihydroxyindole(Poly-DHI)and polydopamine(PDA).Their excellent free radical scavenging capability was further confirmed by the intracellular cell protection effects against reactive oxygen species(ROS)as well as in vivo therapy for acute diseases including acute kidney injury and acute liver injury.This work would promote future work toward new types of melanin-inspired nanomaterials with tunable and improved functions beyond nature.

关键词： melanin condensation polymerization free radical polymerization polydopamine antioxidative-therapy

工作面覆岩采动裂隙演化规律物理及数值模拟研究

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采矿与岩层控制工程学报 2023年第2期5卷 13-22页

作者：王婉洁高富强煤炭科学研究总院有限公司出版传媒集团北京100013 煤炭资源高效开采与洁净利用国家重点实验室(煤炭科学研究总院) 北京100013 中煤科工开采研究院有限公司北京100013

了解工作面推进过程中采动裂隙的演化规律对于煤层气抽采及瓦斯控制至关重要。采用相似模拟和数值模拟的方法研究了工作面推进过程中采空区覆岩采动裂隙的演化规律,研究结果表明:采空区中部和采空区边界处靠近巷道的区域上覆岩层的采动... 详细信息

了解工作面推进过程中采动裂隙的演化规律对于煤层气抽采及瓦斯控制至关重要。采用相似模拟和数值模拟的方法研究了工作面推进过程中采空区覆岩采动裂隙的演化规律,研究结果表明:采空区中部和采空区边界处靠近巷道的区域上覆岩层的采动裂隙存在截然不同的变化规律。采空区中部区域,上覆岩层的采动裂隙随着工作面的移进及越过呈现“迅速增加—逐步减低—稳定”的变化规律;采空区边界靠近巷道的区域,呈现“迅速增加—稳定”的变化规律。远离开切眼、靠近巷道的采空区上覆岩层采动裂隙发育最为充分;工作面走向平行于最大水平主应力时的各区域采动裂隙发育,显著高于工作面走向垂直于最大水平主应力时的;较硬直接顶对于提高采动裂隙渗透率有积极作用。

关键词：采动裂隙瓦斯抽采相似模拟数值模拟

Role of Ppt1 in multiple stress responses in Candida albicans

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Chinese Science Bulletin 2014年第31期59卷 4060-4068页

作者： Kangdi Hu wanjie Li Jiaxin Gao Qizheng Liu Haitao wang Yue wang Jianli Sang Key Laboratory of Cell Proliferation and Regulation Biology Ministry of EducationCollege of Life ScienceBeijing Normal University School of Biotechnology and Food Engineering Hefei University of Technology Institute of Molecular and Cell Biology Agency for ScienceTechnology and Research (A*STAR)

To study the function of CaPpt1,we deleted PPT1 gene from the Candida albicans genome by sequentially replacing the entire coding region with the selectable markers ARG4 and HIS1.The results showed that the deletion of Ppt1 did not affect the hyphal formation of C.albicans under serum induction and caused enhanced sensitivity to DNA damage,Calcofluor white and saltinduced stress.We also found that Ppt1 was not required for the phenotypic response of cells treated with the genotoxins,methylmethane sulfonate and hydroxyurea.Flow cytometric analyses indicated that ppt1D cells and wild-type cells showed similar G2/M arrest profiles when exposed to DNA damage stress.Ppt1 was not required for the activation of the DNA damage response pathway,as indicated by normal phosphorylation of Rad53 and Rfa2 in ppt1D cells under DNA damage stress.We suggest that Ppt1 plays important roles in response to various stress conditions in C.albicans.

关键词：白色念珠菌应激反应流式细胞分析 DNA损伤选择性标记基因组胁迫条件编码区

Study on the viscoelastic behavior of SEEPS block copolymer based on a modified BSW model

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Chinese Science Bulletin 2005年第19期50卷 2171-2175页

作者： wang wanjie ZHENG Qiang YU Qiuming Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China State Key Laboratory of Fluid Power Control and Transmission Zhejiang University Hangzhou 310027 China

Studies on the viscoelastic behavior of styrene- [ethylene-(ethylene-propylene)]-styrene block copolymer (SEEPS) were carried out, and some characteristic viscoelas-tic parameters were calculated. The longest relaxation time τmax was obtained through simulating the relaxation spec-trum on the basis of a modified Baumgaertel-Schausberger- Winter (mBSW) model. The results revealed that there exists a “second plateau” in the low frequency region of the master curves. The reason for this phenomenon is attributed to the entanglement of macromolecular chains. It is suggested that the hard blocks, polystyrene, act as entanglement points, resulting in a topology restraint to the movement of macro-molecular chains. Meanwhile, it is found that the horizontal shift factors (aT) vs temperature in the master curve could be fitted to the Williams-Landel-Ferry (WLF) equation and Ar-rhenius equation respectively and the flow activation energy (Ea) is 127.88 kJ/mol. In addition, the plateau modulus (GN0) and entanglement molecule weight (Me) were calculated.

关键词：苯乙烯共聚物时间温度重合法则黏弹性参数时间光谱频率曲线

CaSfl1 plays a dual role in transcriptional regulation in Candida albicans

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Chinese Science Bulletin 2008年第17期53卷 2624-2631页

作者： ZHANG TingTing LI Di LI wanjie wang Yue SANG JianLi Key Laboratory of Cell Proliferation and Regulation of Ministry of Education Beijing Normal University Beijing 100875 China Candida albicans Molecular and Cell Biology Laboratory Institute of Molecular and Cell Biology Proteos 61 Biopolis Drive Singapore 138673 Singapore

As a newly identified transcription factor in Candida albcians, CaSfl1 has been shown to be involved in cell flocculation and filamentation and in the negative regulation of several genes involved in hyphal growth. In this study, we constructed Casfl1△/△ mutants and confirmed that deletion of this gene indeed affected cell flocculation and filamentation. In addition, by RT-PCR we found that while Casfl1 repressed the expression of several hypha-specific genes including HWP1, ECE1, ALS1, ALS3, and FLO8, it strongly activated the expression of the heat-shock protein genes HSP30 and HSP90 under certain stress conditions. Therefore, we propose that CaSfl1 can act as both positive and negative regulators, thereby playing a dual role in transcriptional controls in Candida albicans.

关键词：假丝酵母 CaSFL1 基因注入形态发生转录规则