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Reinvestigation of liquid crystalline property of dimesogenic compound consisting of cholesterol and cyanobiphenyl

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Chinese Chemical Letters 2009年第9期20卷 1077-1080页

作者： Hai Quan Zhang wen ke liu Li Cheng Zhao Zi Hui Cheng Shuai Zhang Ying Li Huai Yang State key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China Department of Materials Physics and Chemistry School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The dimesogenic compound consisting of cholesterol and cyanobiphenyl mesogens interlinked by ω-oxyalkanoyl spacer was synthesized. The mesomorphic properties were investigated by differential scanning calorimetry （DSC）, polarizing optical microscopy （POM）, and X-ray diffraction （XRD）. The experimental results indicated that this compound exhibited mesophase over a much wider temperature range and a new mesophase blue phase （BP）. Focal conic domains （FCDs） and droplets texture to the smectic A phase （SA）, oily streaks typical to the chiral nematic （N＊） phase were found in the liquid crystalline state, respectively. Besides, it exhibited a smectic layer spacing about 1.0 time to the length of the molecule, which indicated a monolayer type of SA ordering. 2009 Hal Quan Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Dirnesogenic compounds Liquid crystal Cholesteric phase Smectic ordering

Synthesis,liquid crystalline and luminescent properties of trimeric phenylenevinylene with end-groups of(R)-(+)-2-methylbutyric acid ester

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Chinese Chemical Letters 2009年第12期20卷 1423-1426页

作者： Cheng Bo Zhang Ying Li wen ke liu Hai Quan Zhang Huai Yang Qing Shan Li Guang Zhong Xing State key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China Department of Materials Physics and Chemistry School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The trimeric phenylenevinylene with the symmetrical chiral end-groups （ChTPV） was synthesized. The liquid crystalline and luminescent properties of the ChTPV have been studied by differential scanning calorimetry （DSC）, polarized optical microscopy （POM）, absorption and photoluminescence spectra. The results indicated that the ChTPV exhibits mesophase over a wide temperature range and a typical optical texture of smectic phase. In contrast with the spectra of the solution, that of the film showed blue-shift in maximal absorption and red-shift in maximal emission due to H-type aggregation with parallel alignment of the TPV transition dipole moment.

关键词： Trimeric phenylenevinylene Chiral Synthesis Liquid crystalline Luminescence H-type aggregation

Mesh-supported V2O5-WO3/TiO2 nanosheet array catalysts for efficient removal of NOx

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Tungsten 2025年第1期7卷 100-111页

作者： Zhi-Qi Zhang liu Yang wen Luo Vladimir An Jing Li Bao-Dan liu School of Materials Science and Engineering Northeastern University Foshan Graduate School of Innovation Northeastern University Kizhner Research Center School of Advanced Manufacturing Technologies Tomsk Polytechnic University

The design and synthesis of vanadium-based denitration catalysts with low-temperature activity pose significant challenges in the field of toxic gas *** this study,we have developed a novel approach to fabricate highly efficient V2O5-WO3/TiO2monolithic mesh catalysts for NOxreduction at low ***,TiO2nanosheets with strong adhesion and large surface area were grown on Ti mesh using plasma electrolytic oxidation technology and hydrothermal ***,super-small traces of WO3and V2O5active nano-species were subsequently deposited on TiO2nanosheets using the deposition-precipitation *** to traditional ceramic-based V2O5-WO3/TiO2catalysts,our V2O5-WO3/TiO2monolithic mesh catalyst exhibits superior mechanical performance,excellent thermal conductivity,lower pressure drop,higher utilization of active components,and stronger synergistic ***,the V2O5-WO3/TiO2monolithic mesh catalysts exhibited excellent low-temperature catalytic activity with 98% of NOxconversion at 220℃,and remarkable long-term SO2tolerance and water resistance in the selective catalytic reduction（SCR） of NOxwith *** SCR reaction of tiny V2O5and WO3active species supported on TiO2nanosheets directly demonstrated to follow the Eley-Rideal mechanism by in situ infrared spectra.

关键词： Low temperature activity Monolithic mesh catalysts NH3-SCR SO2 tolerance V2O5-WO3/TiO2

PI3K/AKT signaling and neuroprotection in ischemic stroke:molecular mechanisms and therapeutic perspectives

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Neural Regeneration Research 2025年第10期20卷 2758-2775页

作者： Tianlong liu Xiaolin Li Xiaowei Zhou Wei Chen Aidong wen Minna liu Yi Ding Department of Pharmacy Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Pharmacy The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina Department of Pharmacy The 944 Hospital of Joint Logistics Support Forces of Chinese PLAJiuquanGansu ProvinceChina Department of Nephrology The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina

It has been reported that the PI3K/AKT signaling pathway plays a key role in the pathogenesis of ischemic *** a result,the development of drugs targeting the PI3K/AKT signaling pathway has attracted increasing attention from *** article reviews the pathological mechanisms and advancements in research related to the signaling pathways in ischemic stroke,with a focus on the PI3K/AKT signaling *** key findings include the following:(1)The complex pathological mechanisms of ischemic stroke can be categorized into five major types:excitatory amino acid toxicity,Ca^(2+)overload,inflammatory response,oxidative stress,and apoptosis.(2)The PI3K/AKT-mediated signaling pathway is closely associated with the occurrence and progression of ischemic stroke,which primarily involves the NF-κB,NRF2,BCL-2,mTOR,and endothelial NOS signaling pathways.(3)Natural products,including flavonoids,quinones,alkaloids,phenylpropanoids,phenols,terpenoids,and iridoids,show great potential as candidate substances for the development of innovative anti-stroke medications.(4)Recently,novel therapeutic techniques,such as electroacupuncture and mesenchymal stem cell therapy,have demonstrated the potential to improve stroke outcomes by activating the PI3K/AKT signaling pathway,providing new possibilities for the treatment and rehabilitation of patients with ischemic *** investigations should focus on the direct regulatory mechanisms of drugs targeting the PI3K/AKT signaling pathway and their clinical translation to develop innovative treatment strategies for ischemic stroke.

关键词： apoptosis autophagy inflammation ischemic stroke neuroprotection oxidative stress pathogenesis phosphatidylinositol 3-kinase protein kinase B therapeutics

Actively tunable electromagnetically induced transparency in hybrid Dirac-VO2 metamaterials

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Optoelectronics Letters 2025年第1期21卷 13-20页

作者： DI ke XIE Meng XIA Huarong CHENG Anyu liu Yu DU Jiajia Department of Optoelectronic Engineering Chongqing University of Post and Telecommunications Chongqing key Laboratory of Autonomous Navigation and Microsystem Chongqing University of Posts and Telecommunications Department of Automation Chongqing University of Post and Telecommunications

In this paper, we present a metamaterial structure of Dirac and vanadium dioxide（VO2） and investigate its optical properties using the finite-difference time-domain（FDTD） technique. Using the phase transition feature of VO2, the design can realize active tuning of the plasmon induced transparency（PIT） effect at terahertz frequency, thereby converting from a single PIT to a double-PIT. When VO2is in the insulating state, the structure is symmetric to obtain a single-band PIT effect. When VO2is in the metallic state, the structure turns asymmetric to realize a dual-band PIT effect. This design provides a reference direction for the design of actively tunable metamaterials. Additionally, it is discovered that the transparent window's resonant frequency and the Fermi level in this structure have a somewhat linear relationship. In addition, the structure achieves superior refractive index sensitivity in the terahertz band, surpassing 1 THz/RIU. Consequently, the design exhibits encouraging potential for application in refractive index sensors and optical switches.

关键词： Transparency

Engineered Cancer Nanovaccines:A New Frontier in Cancer Therapy

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Nano-Micro Letters 2025年第2期17卷 134-168页

作者： Yijie Wang Congrui liu Chao Fang Qiuxia Peng wen Qin Xuebing Yan Kun Zhang Central Laboratory and Department of Medical Ultrasound Sichuan Academy of Medical SciencesSichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaNo.32West Second SectionFirst Ring RoadChengdu 610072People’s Republic of China Department of Stomatology and Central Laboratory School of MedicineShanghai Tenth People’s HospitalTongji UniversityNO.301 Yan‑Chang‑Zhong RoadShanghai 200072People’s Republic of China Jiangsu Provincial Innovation and Practice Base for Postdoctors Suining People’s HospitalAffiliated Hospital of Xuzhou Medical UniversityNo.2Bayi West RoadSuiningXu Zhou 221000Jiangsu ProvincePeople’s Republic of China

Vaccinations are essential for preventing and treating disease,especially cancer nanovaccines,which have gained considerable interest recently for their strong anti-tumor immune *** can prompt the immune system to generate antibodies and activate various immune cells,leading to a response against tumor tissues and reducing the negative effects and recurrence risks of traditional chemotherapy and *** enhance the flexibility and targeting of vaccines,nanovaccines utilize nanotechnology to encapsulate or carry antigens at the nanoscale level,enabling more controlled and precise drug delivery to enhance immune *** nanovaccines function by encapsulating tumor-specific antigens or tumor-associated antigens within *** small size of these nanomaterials allows for precise targeting of T cells,dendritic cells,or cancer cells,thereby eliciting a more potent anti-tumor *** this paper,we focus on the classification of carriers for cancer nanovaccines,the roles of different target cells,and clinically tested cancer nanovaccines,discussing strategies for effectively inducing cytotoxic T lymphocytes responses and optimizing antigen presentation,while also looking ahead to the translational challenges of moving from animal experiments to clinical trials.

关键词： Cancer nanovaccines Immunotherapy Nanobiotechnology Immune targets Signaling pathway

Visualization of the protective role of estrogen against female liver fibrosis via an ER viscosity NIR fluorescent probe

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Science China Chemistry 2025年第1期68卷 360-368页

作者： Zheng liu Changyu Zhang Zipeng Li Wanying Ma Jia liu Xiang Xia Ning Xu wen Sun Jianjun Du Jiangli Fan Xiaojun Peng State key Laboratory of Fine Chemicals Dalian University of Technology Ningbo Institute of Dalian University of Technology

Endoplasmic reticulum(ER) viscosity has emerged as a new potential biomarker for hepatic fibrosis(HF). Herein, we report the first ER-targeting viscosity-responsive near-infrared(NIR) fluorescent probe HBT-PP for investigations of HF *** twisted intramolecular charge transfer(TICT) and the excited state intramolecular proton transfer(ESIPT) are combined to endow HBT-PP with the selective response towards viscosity(～62-fold) and a super large stokes shift(～320 nm). HBT-PP mainly targets organelle ER and is able to image the drug-or alcohol-induced viscosity elevation in living cells. Significantly,HBT-PP was successfully applied to visualize the gender difference in HF and the protective role of estrogen in restraining HF progression. Of note, after 10 min of stain with HBT-PP, HF lesions showed a stage-based response, indicating the potential of this probe in fast and early diagnosis of HF. These results clearly demonstrated the promising application of HBT-PP as a new tool for exploring ER viscosity-involved physiological and pathological processes.

关键词： NIR fluorescent probe ER viscosity hepatic fibrosis gender difference estrogen

Broadband and perfect terahertz absorber based on multilayer metamaterial with cross-ring patterned structures

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Optoelectronics Letters 2025年第1期21卷 1-6页

作者： wen Jin liu Zhanzhi WU Zhengwei PAN Yu ZHANG Ying School of Science Xi'an Shiyou University Shaanxi key Laboratory of Measurement and Control Technology for Oil and Gas Wells

Broadband and perfect terahertz absorber based on multilayer metamaterial using cross-ring patterned structures is proposed and investigated. The structure of the absorber is double absorption layers consisting of a chromium cross ring and eight isosceles right triangles. The unique structure of the double absorbing layers excites the electric dipole multimode resonance, giving rise to high absorption performance. Meanwhile, the influence of construal parameters on absorber behavior is also discussed. The numerical results show that the absorption achieves over 90% ranging from 2.45 THz to 6.25 THz and 99% absorption in the range of 3.7—5.3 THz. The realization of broadband and perfect absorber is described using the impedance matching principle. It is obviously found that the absorber is insensitive to the high angle of incidence for both transverse electric(TE) and transverse magnetic(TM) polarizations. Compared with the former reports, this absorber has remarkable improved absorption efficiency and smaller period. The terahertz absorber may be found applications in the fields of energy capture and thermal detection.

关键词： Metamaterials

Future development research of 5G positioning in 3GPP standards

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The Journal of China Universities of Posts and Telecommunications 2025年

作者： liu wen Ren Hailong Deng Zhongliang School of Electronic Engineering， Beijing University of Posts and Telecommunications

Since the release of the first version of the 5th Generation Mobile Networks (5G) standard， Release-15 (Rel-15)， in June 2018， the 3rd Generation Partnership Project (3GPP) made significant efforts in the field of indoor and outdoor wireless positioning. Notably， Release-16 augmented support for enhanced mobile broadband (eMBB) and ultra-reliable low-latency communication (uRLLC)， particularly within complex indoor settings. To further meet the diverse application needs of positioning scenarios， the 3GPP standards for Release-17 and Release-18 propose new enhancement measures to continuously provide more accurate positioning services. In this paper， the scholarly discourse on 5G positioning was critically examined， providing a systematic review of the 5G positioning standards as delineated in 3GPP's Release-16 and Release-17， and was extended the discussion to the anticipated enhancements in 5G Release-18， along with their underlying motivations. Through these discussions， this article not only a comprehensive perspective on the current development of 5G positioning technology was provided but also was offered forward-looking analysis and predictions for the evolution of positioning technology in the upcoming 3GPP Release-19 phase. Additionally， it serves as a reference for researchers interested in understanding the development of positioning within the standard framework in the field of 5G indoor positioning， which holds significant meaning for promoting research and application of 5G positioning technology.

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