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薄膜润滑 5

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Enhanced photoelectrochemical water splitting with a donor-acceptor polyimide

《能源前沿（英文）》 doi: 10.1007/s11708-023-0910-8

摘要： Polyimide (PI) has emerged as a promising organic photocatalyst owing to its distinct advantages of high visible-light response, facile synthesis, molecularly tunable donor-acceptor structure, and excellent physicochemical stability. However, the synthesis of high-quality PI photoelectrode remains a challenge, and photoelectrochemical (PEC) water splitting for PI has been less studied. Herein, the synthesis of uniform PI photoelectrode films via a simple spin-coating method was reported, and their PEC properties were investigated using melamine as donor and various anhydrides as acceptors. The influence of the conjugate size of aromatic unit (phenyl, biphenyl, naphthalene, perylene) of electron acceptor on PEC performance were studied, where naphthalene-based PI photoelectrode exhibited the highest photocurrent response. This is resulted from the unification of wide-range light absorption, efficient charge separation and transport, and strong photooxidation capacity. This paper expands the material library of polymer films for PEC applications and contributes to the rational design of efficient polymer photoelectrodes.

关键词： polyimide (PI) film     photoelectrochemistry     band structure engineering     aromatic unit    

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Preparation and characterization of polyimide/silica/silver composite films

JIANG Lizhong, WU Dezhen, LUO Ning, WU Zhanpeng, MOU Nanxiang

《化学科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 291-295 doi: 10.1007/s11705-008-0059-3

摘要： Polyimide/silica/silver hybrid films were prepared by the sol-gel method combined with single-stage self-metallization technique. The structure of polyimide films in the thermal curing process and the influence of silica content on the migration and aggregation of silver particles to the surface of hybrid films were investigated. The hybrid films were characterized by transmission electron microscopy, dynamic mechanical thermal analysis, Fourier transform infrared spectroscopy, ultraviolet visible spectroscopy and mechanical measurements. The results indicated that there was no degradation of the polyimide matrix after the formation of silica and silver particles. Silica acted as the nucleus for the silver particles. With increasing silica content, more and more silver particles were kept in the hybrid films instead of being migrated onto the surface of the hybrid films and the reflections of hybrid films decreased gradually.

关键词： single-stage self-metallization     spectroscopy     transmission     Polyimide/silica/silver     ultraviolet visible    

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Multi-effect anthraquinone-based polyimide enclosed SnO/reduced graphene oxide composite as high-performance

《化学科学与工程前沿（英文）》 2023年 第17卷 第9期   页码 1231-1243 doi: 10.1007/s11705-023-2306-z

摘要： The cycling stability of SnO2 anode as lithium-ion battery is poor due to volume expansion. Polyimide coatings can effectively confine the expansion of SnO2. However, linear polyimides are easily dissolved in ester electrolytes and their carbonyls is not fully utilized during charging/discharging process. Herein, the SnO2 enclosed with anthraquinone-based polyimide/reduced graphene oxide composite was prepared by self-assembly. Carbonyls from the anthraquinone unit provide fully available active sites to react with Li+, improving the utilization of carbonyl in the polyimide. More exposed carbonyl active sites promote the conversion of Sn to SnO2 with electrode gradual activation, leading to an increase in reversible capacity during the charge/discharge cycle. In addition, the introduction of reduced graphene oxide cannot only improve the stability of polyimide in the electrolyte, but also build fast ion and electron transport channels for composite electrodes. Due to the multiple effects of anthraquinone-based polyimide and the synergistic effect of reducing graphene oxide, the composite anode exhibits a maximum reversible capacity of 1266 mAh·g−1 at 0.25 A·g−1, and maintains an excellent specific capacity of 983 mAh·g−1 after 200 cycles. This work provides a new strategy for the synergistic modification of SnO2.

关键词： anthraquinone-based polyimide     multi-effect     tin dioxide     reduced graphene oxide     lithium-ion battery    

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4Pi荧光超分辨显微术综述 Review

郝翔, 李依明, 傅爽, 李旸晖, 许迎科, 匡翠方, 刘旭

《工程（英文）》 2022年 第11卷 第4期   页码 146-153 doi: 10.1016/j.eng.2020.07.028

摘要： 回顾这些历程，一个重要的里程碑是基于两个对置物镜的4Pi 显微架构及其超分辨版本的出现。鉴于此，本文综述了4Pi 超分辨显微术的近期进展。总体上，4Pi 超分辨显微镜为透明样品观测提供了一
种能够突破衍射极限、非侵入、各向同性的三维分辨率的技术手段。具体而言，本文针对目标开关和随机开关两个主要4Pi 超分辨显微术版本，讨论了它们的架构、原理、应用和未来发展趋势。

关键词： 荧光超分辨显微术     超分辨成像     4Pi超分辨显微术     isoSTED     4Pi-SMLM    

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RGS16 regulated by let-7c-5p promotes glioma progression by activating PI3K-AKT pathway

《医学前沿（英文）》 2023年 第17卷 第1期   页码 143-155 doi: 10.1007/s11684-022-0929-y

摘要： Gliomas are the most common central nervous system tumours; they are highly aggressive and have a poor prognosis. RGS16 belongs to the regulator of G-protein signalling (RGS) protein family, which plays an important role in promoting various cancers, such as breast cancer, pancreatic cancer, and colorectal cancer. Moreover, previous studies confirmed that let-7c-5p, a well-known microRNA, can act as a tumour suppressor to regulate the progression of various tumours by inhibiting the expression of its target genes. However, whether RGS16 can promote the progression of glioma and whether it is regulated by miR let-7c-5p are still unknown. Here, we confirmed that RGS16 is upregulated in glioma tissues and that high expression of RGS16 is associated with poor survival. Ectopic deletion of RGS16 significantly suppressed glioma cell proliferation and migration both in vitro and in vivo. Moreover, RGS16 was validated as a direct target gene of miR let-7c-5p. The overexpression of miR let-7c-5p obviously downregulated the expression of RGS16, and knocking down miR let-7c-5p had the opposite effect. Thus, we suggest that the suppression of RGS16 by miR let-7c-5p can promote glioma progression and may serve as a potential prognostic biomarker and therapeutic target in glioma.

关键词： RGS16     let-7c-5p     glioma     proliferation     migration    

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Dielectric property of polyimide/barium titanate composites and its influence factors (II)

LIU Weidong, ZHU Baoku, XIE Shuhui, XU Zhikang

《化学科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 417-421 doi: 10.1007/s11705-008-0078-0

摘要： Using poly(amic acid) (PAA) as a precursor followed by thermal imidization, the polyimide/barium titanate composite films were successfully prepared by a direct mixing method and in situ process. The influence of processing factors, such as particle size, distribution mode and polymerization method on dielectric properties was studied. Results revealed that the dielectric constant (?) of the composite film increased by using bigger fillers or employing in situ polymerization and bimodal distribution. When the composite film containing 50 Vol-% of BaTiO with size in 100 nm was prepared via in situ process, its dielectric constant reached 45 at 10 kHz.

关键词： thermal imidization     dielectric constant     particle     precursor     titanate composite    

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Molecular level understanding of CO2 capture in ionic liquid/polyimide composite membrane

Linlin You, Yandong Guo, Yanjing He, Feng Huo, Shaojuan Zeng, Chunshan Li, Xiangping Zhang, Xiaochun Zhang

《化学科学与工程前沿（英文）》 2022年 第16卷 第2期   页码 141-151 doi: 10.1007/s11705-020-2009-7

摘要： Ionic liquid (IL)/polyimide (PI) composite membranes demonstrate promise for use in CO separation applications. However, few studies have focused on the microscopic mechanism of CO in these composite systems, which is important information for designing new membranes. In this work, a series of systems of CO in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide composited with 4,4-(hexafluoroisopropylidene) diphthalic anhydride (6FDA)-based PI, 6FDA-2,3,5,6-tetramethyl-1,4-phenylene-diamine, at different IL concentrations were investigated by all-atom molecular dynamics simulation. The formation of IL regions in PI was found, and the IL regions gradually became continuous channels with increasing IL concentrations. The analysis of the radial distribution functions and hydrogen bond numbers demonstrated that PI had a stronger interaction with cations than anions. However, the hydrogen bonds among PI chains were destroyed by the addition of IL, which was favorable for transporting CO . Furthermore, the self-diffusion coefficient and free energy barrier suggested that the diffusion coefficient of CO decreased with increasing IL concentrations up to 35 wt-% due to the decrease of the fractional free volume of the composite membrane. However, the CO self-diffusion coefficients increased when the IL contents were higher than 35 wt-%, which was attributed to the formation of continuous IL domain that benefitted the transportation of CO .

关键词： carbon dioxide     ionic liquid     6FDA-TeMPD     composite membrane     molecular dynamics simulation    

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Numerical simulation of liquid falling film on horizontal circular tubes

Fengdan SUN, Songlin XU, Yongchuan GAO

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 322-328 doi: 10.1007/s11705-012-1296-z

摘要： The objective of this study is to investigate numerically the flow characteristics of falling film on horizontal circular tubes. Numerical simulations are performed using FLUENT for 2D configurations with one and two cylinders. The volume of fluid method is used to track the motion of liquid falling film and the gas-liquid interface. The effect of flow characteristics on heat and transfer coefficient may be remarkable, although it has been neglected in previous studies. The velocity distribution and the film thickness characteristics on the top tube, some special flow characteristics on the bottom tube, intertube flow modes and effect of liquid feeder height on flow characteristics have been studied. Our simulations indicate that 1) the velocity distributions of the upper and lower parts of the tube are not strictly symmetric and non-uniform, 2) the film thickness depends on flow rate and angular distributions, 3) the flow characteristics of the top tube are different from those of the bottom tube, 4) three principal and two intermediate transition modes are distinguished, and 5) the liquid feed height plays an important role on the formation of falling film. The numerical results are in a good agreement with the theoretical values by the Nusselt model and the reported results.

关键词： falling film     horizontal tube     flow characteristics     film thickness     liquid feeder height    

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Experiment and optimal design of a collection device for a residual plastic film baler

Qi NIU,Xuegeng CHEN,Chao JI,Jie WU

《农业科学与工程前沿（英文）》 2015年 第2卷 第4期   页码 347-354 doi: 10.15302/J-FASE-2015077

摘要： It is imperative to carry out research on residual plastic film collection technology to solve the serious problem of farmland pollution. The residual plastic film baler was designed as a package for film strip collection, cleaning and baling. The collection device is a core component of the baler. Response surface analysis was used in this study to optimize the structure and working parameters for improving the collection efficiency of residual film and the impurity of film package. The results show that the factors affecting the collection rate of residual film and the impurity of the film package are the speed ratio ( ) between the trash removal roller and eccentric collection mechanism, the number ( ) and the mounting angle ( ) of spring teeth in the same revolution plane. For the collection rate, the importance of the three factors are in the order, . Meanwhile, for the impurity, the importance of three factors are in the order, . When the speed ratio, the mounting angle and the number of spring teeth was set at 1.6°, 45°, and 8°, respectively, the collection rate of residual film was 88.9% and the impurity of residual film package was 14.2% for the baler.

关键词： residual film     collection device     collection rate of residual film     impurity of film package     optimization     baler    

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薄膜润滑研究的回顾与展望

雒建斌,张朝辉,温诗铸

《中国工程科学》 2003年 第5卷 第7期   页码 84-89

摘要：

薄膜润滑是20世纪90年代以来广泛研究的新型润滑状态。它是界于弹流润滑和边界润滑之间的一种过渡润滑状态，有着自己独特的润滑规律。文章回顾了薄膜润滑的研究历史，包括薄膜润滑概念的提出、测试技术的发展、薄膜润滑的膜厚特性、润滑机理探索以及计算理论等方面的研究成果与主要进展。

关键词： 薄膜润滑     有序膜     膜厚测量     微结构    

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Thin-liquid-film evaporation at contact line

Hao WANG, Zhenai PAN, Zhao CHEN

《能源前沿（英文）》 2009年 第3卷 第2期   页码 141-151 doi: 10.1007/s11708-009-0020-2

摘要： When a liquid wets a solid wall, the extended meniscus near the contact line may be divided into three regions: a nonevaporating region, where the liquid is adsorbed on the wall; a transition region or thin-film region, where effects of long-range molecular forces (disjoining pressure) are felt; and an intrinsic meniscus region, where capillary forces dominate. The thin liquid film, with thickness from nanometers up to micrometers, covering the transition region and part of intrinsic meniscus, is gaining interest due to its high heat transfer rates. In this paper, a review was made of the researches on thin-liquid-film evaporation. The major characteristics of thin film, thin-film modeling based on continuum theory, simulations based on molecular dynamics, and thin-film profile and temperature measurements were summarized.

关键词： meniscus     thin film     contact line     disjoining pressure     evaporation    

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Xiao Ke Qing improves glycometabolism and ameliorates insulin resistance by regulating the PI3K/Akt pathway

Xiaoqing Li, Xinxin Li, Genbei Wang, Yan Xu, Yuanyuan Wang, Ruijia Hao, Xiaohui Ma

《医学前沿（英文）》 2018年 第12卷 第6期   页码 688-696 doi: 10.1007/s11684-018-0662-8

摘要：

Xiao Ke Qing (XKQ) granule has been clinically used to treat type 2 diabetes mellitus (T2DM) for 10 years in Chinese traditional medication. However, its mechanisms against hyperglycemia remain poorly understood. This study aims to investigate XKQ mechanisms on diabetes and diabetic liver disease by using the KKAy mice model. Our results indicate that XKQ can significantly reduce food and water intake. XKQ treatment also remarkably decreases both the fasting blood glucose and blood glucose in the oral glucose tolerance test. Additionally, XKQ can significantly decrease the serum alanine aminotransferase level and liver index and can alleviate the fat degeneration in liver tissues. Moreover, XKQ can ameliorate insulin resistance and upregulate the expression of IRS-1, PI3K (p85), p-Akt, and GLUT4 in the skeletal muscle of KKAy mice. XKQ is an effective drug for T2DM by ameliorating insulin resistance and regulating the PI3K/Akt signaling pathway in the skeletal muscle.

关键词： XKQ     type 2 diabetes mellitus     KKAy mice     PI3K/Akt pathway     diabetic liver disease    

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Ultraviolet-B induced expression of hypoxia-inducible factor 1α, transferrin receptor through EGFR/PI3K

LI Yanhua, BI Zhigang

《医学前沿（英文）》 2007年 第1卷 第1期   页码 79-86 doi: 10.1007/s11684-007-0016-4

摘要： The aim of this research was to explore the effects and signaling pathway of ultraviolet-B (UVB) irradiation on the expression of hypoxia-inducible factor 1α (HIF-1α) and transferrin receptor (TfR). HIF-1α protein was measured by Western blot method. Expressions of epidermal growth factor receptor (EGFR), phosphor-EGF-R and TfR after UVB irradiation were determined with flow cytometry. After UVB irradiation, mRNA levels of HIF-1α and TfR were detected by real time-PCR. Results showed that compared with control groups, UVB was able to induce HIF1α and TfR protein expression in a dose- and time-dependent manner in HaCat cells (<0.05). TfR mRNA was expressed in a dose-dependent manner and reached a peak at the 8th hour in HaCat cells (<0.05) whereas HIF-1α mRNA expression was not affected by UVB treatment (>0.05). The EGFR/PI3K/AKT signaling pathway was required for the induction of HIF-1α and TfR expression induced by UVB. UVB induced activation of EGFR in HaCat cells and EGFR regulated expression of TfR and HIF-1α. EGFR (-/-) MEF did not increase the HIF1 expression following UVB irradiation (>0.05). In contrast, EGFR (+/+) MEF strongly enhanced HIF1α expression after UVB irradiation (<0.05). PD153035, a selective inhibitor of EGFR tyrosine kinase, inhibited the TfR protein expression in UVB-treated cells in a dose-dependent manner (P<0.05). PI3K inhibitors, LY294002 and wortmannin, inhibited HIF-1? and TfR expressions induced by UVB (P<0.05). The DEC1 (-/-) Ha-Cat cells did not increase their TfR and HIF-1α expressions following UVB irradiation (>0.05). In contrast, DEC1 (+/+) HaCat cells strongly enhanced TfR and HIF-1? protein expression after UVB irradiation (P<0.05). We conclude that UVB induces TfR and HIF-1αexpressions via EGFR/PI3K/AKT/DEC1 signaling pathway.
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Surface-tailoring chlorine resistant materials and strategies for polyamide thin film composite reverse

《化学科学与工程前沿（英文）》 2022年 第16卷 第5期   页码 564-591 doi: 10.1007/s11705-021-2109-z

摘要： Polyamide thin film composite membranes have dominated current reverse osmosis market on account of their excellent separation performances compared to the integrally skinned counterparts. Despite their very promising separation performance, chlorine-induced degradation resulted from the susceptibility of polyamide toward chlorine attack has been regarded as the Achilles’s heel of polyamide thin film composite. The free chlorine species present during chlorine treatment can impair membrane performance through chlorination and depolymerization of the polyamide selective layer. From material point of view, a chemically stable membrane is crucial for the sustainable application of membrane separation process as it warrants a longer membrane lifespan and reduces the cost involved in membrane replacement. Various strategies, particularly those involved membrane material optimization and surface modifications, have been established to address this issue. This review discusses membrane degradation by free chlorine attack and its correlation with the surface chemistry of polyamide. The advancement in the development of chlorine resistant polyamide thin film composite membranes is reviewed based on the state-of-the-art surface modifications and tailoring approaches which include the in situ and post-fabrication membrane modifications using a broad range of functional materials. The challenges and future directions in this field are also highlighted.

关键词： reverse osmosis     polyamide     thin film composite membranes     chlorine resistance     surface modification    

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Piezoelectric film-actuated motion platform with high resolution

HUA Shunming, ZHANG Hongzhuang, CHENG Guangming, FAN Zunqiang, LIU Jianfang

《机械工程前沿（英文）》 2008年 第3卷 第3期   页码 265-269 doi: 10.1007/s11465-008-0041-2

摘要： A piezoelectric film-actuated motion platform with high resolution, which can run in two directions within a horizontal plane, is presented. On the basis of the analysis of the working principle of a stick-slip mechanism, a mathematical model describing its dynamic behavior is set up and simulated. Experiments of the motion performance and carrying ability on the prototype are conducted. Results show that this type of platform has advantages including a simple structure, small volume, light weight, stable step length, and large traveling range. When the driving voltage is less than 30 V, step error is less than 0.5 ?m. The carrying ability of the platform is terrific and about 7–8 times its weight.

关键词： mathematical     stick-slip mechanism     piezoelectric film-actuated     analysis     terrific    

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标题 作者 时间 类型 操作

Enhanced photoelectrochemical water splitting with a donor-acceptor polyimide

期刊论文

Preparation and characterization of polyimide/silica/silver composite films

JIANG Lizhong, WU Dezhen, LUO Ning, WU Zhanpeng, MOU Nanxiang

期刊论文

Multi-effect anthraquinone-based polyimide enclosed SnO/reduced graphene oxide composite as high-performance

期刊论文

4Pi荧光超分辨显微术综述

郝翔, 李依明, 傅爽, 李旸晖, 许迎科, 匡翠方, 刘旭

期刊论文

RGS16 regulated by let-7c-5p promotes glioma progression by activating PI3K-AKT pathway

期刊论文

Dielectric property of polyimide/barium titanate composites and its influence factors (II)

LIU Weidong, ZHU Baoku, XIE Shuhui, XU Zhikang

期刊论文

Molecular level understanding of CO2 capture in ionic liquid/polyimide composite membrane

Linlin You, Yandong Guo, Yanjing He, Feng Huo, Shaojuan Zeng, Chunshan Li, Xiangping Zhang, Xiaochun Zhang

期刊论文

Numerical simulation of liquid falling film on horizontal circular tubes

Fengdan SUN, Songlin XU, Yongchuan GAO

期刊论文

Experiment and optimal design of a collection device for a residual plastic film baler

Qi NIU,Xuegeng CHEN,Chao JI,Jie WU

期刊论文

薄膜润滑研究的回顾与展望

雒建斌,张朝辉,温诗铸

期刊论文

Thin-liquid-film evaporation at contact line

Hao WANG, Zhenai PAN, Zhao CHEN

期刊论文

Xiao Ke Qing improves glycometabolism and ameliorates insulin resistance by regulating the PI3K/Akt pathway

Xiaoqing Li, Xinxin Li, Genbei Wang, Yan Xu, Yuanyuan Wang, Ruijia Hao, Xiaohui Ma

期刊论文

Ultraviolet-B induced expression of hypoxia-inducible factor 1α, transferrin receptor through EGFR/PI3K

LI Yanhua, BI Zhigang

期刊论文

Surface-tailoring chlorine resistant materials and strategies for polyamide thin film composite reverse

期刊论文

Piezoelectric film-actuated motion platform with high resolution

HUA Shunming, ZHANG Hongzhuang, CHENG Guangming, FAN Zunqiang, LIU Jianfang

期刊论文