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Research Progress in the Fabrication of Covalent Organic Framework Membranes for Chemical Separations

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Chinese Journal of Polymer Science 2024年第2期42卷 141-158,I0005页

作者： Cui-Ting Ding Jin-Qiu yuan Meng-Ying Xie Qing-yuan Liu Zeng-Guang Yao shi-yu zhang Run-Nan zhang Hong Wu Zhong-Yi Jiang Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China Zhejiang Institute of Tianjin University NingboZhejiang315201China Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China Tianjin Key Laboratory of Membrane Science and Desalination Technology Tianjin UniversityTianjin300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou350207China

Membrane technology has become one of the most promising separation technologies for its energy saving, high separation efficiency, environmental friendliness, and economic feasibility. Covalent organic frameworks(COFs) with intrinsically high porosity, controllable pore size, uniform pore size distribution and long-range ordered channel structure, have emerged as next-generation materials to fabricate advanced separation membranes. This feature article summarizes some latest studies in the development of pure COF membranes in our lab, including their fabrication and applications in chemical separations. Finally, current challenges facing high-performance COF separation membranes are discussed.

关键词： Covalent organic frameworks Covalent organic framework membranes Water treatment Organic solvent nanofiltration Gas separation

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中国香港与内地入境旅游市场演化特征与差异

江苏商论 2024年第5期 47-50,77页

作者：齐文权石张宇浙江工商大学旅游与城乡规划学院浙江杭州310018 浙江工商大学杭州商学院浙江杭州311508

入境旅游是反映一个国家(地区)旅游吸引力、国际化水平的重要标志。为科学探究中国香港和内地入境旅游市场特征,基于改进的“旅游O-D”优化模型,本文从内外双视角、多维度指标对比分析两地入境客源市场的集中化和多样性特征与差异。结... 详细信息

入境旅游是反映一个国家(地区)旅游吸引力、国际化水平的重要标志。为科学探究中国香港和内地入境旅游市场特征,基于改进的“旅游O-D”优化模型,本文从内外双视角、多维度指标对比分析两地入境客源市场的集中化和多样性特征与差异。结果显示,从内部来看,两地市场集中度均较高,但中国香港仍在不断小幅提升;内地则有所降低即多样化程度提高。两地互为对方首位市场,客源地重叠度较高,但中国香港过度依赖内地市场。从外部来看,两地“高高”“高低”市场特征相似,互为双方的双高市场,“高低”市场全为欧美国家,“低高”市场主要为中国澳门和日、蒙、菲等亚洲国家。从内外部结合来看,两地双高市场变动不大,内地一直为中国香港唯一的双高市场,而中国港澳台、韩长期为内地的双高市场,两地均无“高低”市场,双低市场数量均占比过大。市场集中化与多样性战略并无优劣之分,还要重视市场规模和持续、稳定的增长能力。内地和中国香港入境旅游在提升质量的同时,也要密切关注规模数量的增长,加强合作,共拓客源,吸引更多的外国游客经内地访港或经港访内地,提高外国游客总量,优化外国客源市场结构,推动中国入境旅游高质量发展。

关键词：入境旅游市场集中化与多样性差异内地中国香港

Hi'CT:a pixel sensor-based device for ion tomography

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Nuclear Science and Techniques 2023年第7期34卷 231-241页

作者： Yi-Lun Chen Hong-Kai Wang shi-yu zhang Hai-Bo Yang Cheng-Xin Zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516003China

Carbon ions,commonly referred to as particle therapy,have become increasingly popular in the last *** predicting the range of ions in tissues is important for the precise delivery of doses in heavy-ion *** uncertainty is currently the largest contributor to dose uncertainty in normal tissues,leading to the use of safety margins in treatment *** potential method is the direct relative stopping measurement(RSP)with ***-ion CT(Hi′CT),a compact segmented full digital tomography detector using monolithic active pixel sensors,was designed and evaluated using a 430 MeV/u high-energy carbon ion pencil beam in *** precise position of the individual carbon ion track can be recorded and reconstructed using a 30μm×30μm small pixel pitch *** types of customized image reconstruction algorithms were developed,and their performances were evaluated using three different modules of CAT-PHAN 600-series *** RSP measurement accuracy of the tracking algorithm for different types of materials in the CTP404 module was less than 1%.In terms of spatial resolution,the tracking algorithm could achieve a 20%modulation transfer function normalization value of CTP528 imaging results at 5 lp/cm,which is significantly better than that of the fast imaging algorithm(3 lp/cm).The density resolution obtained using the tracking algorithm of the customized CTP515 was approximately 10.5%.In conclusion,a compact digital Hi'CT system was designed,and its nominal performance was evaluated in a *** RSP resolution and image quality provide potential feasibility for scanning most parts of an adult body or pediatric patient,particularly for head and neck tumor treatment.

关键词： Heavy-ion imaging Computed tomography Silicon pixel detectors Monte Carlo Phantoms Radiotherapy Image-guided Tracking

103 GHz germanium-on-silicon photodiode enabled by an optimized U-shaped electrode

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Photonics Research 2024年第1期12卷 1-6页

作者： Yang shi Xiang Li Mingjie Zou yu yu Xinliang zhang Wuhan National Laboratory for Optoelectronics&School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Engineering and Electronic Information China University of GeosciencesWuhan 430074China Optics Valley Laboratory Wuhan 430074China Xidian University Xi’an 710126China

High-performance germanium photodiodes are crucial components in silicon photonic integrated circuits for large-capacity data ***,the bandwidths of most germanium photodiodes are limited by the intractable resistance–capacitance parasitic ***,we introduce a unique U-shaped electrode to alleviate this issue,reducing the parasitic effect by 36%without compromising any other ***,a large bandwidth of 103 GHz,an optical responsivity of 0.95 A/W at 1550 nm,and a dark current as low as 1.3 nA are achieved,leading to a record high specific *** is the first breakthrough to 100 GHz bandwidth among all vertical germanium photodiodes,to the best of our *** eye diagrams of 120 Gb/s on-off keying and 200 Gb/s four-level pulse amplitude signals are well *** work provides a promising solution for chip-based ultra-fast photodetection.

关键词： Gb/s shaped electrode

Design and synthesis of liquid crystal copolyesters with high-frequency low dielectric loss and inherent flame retardancy

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Chinese Chemical Letters 2023年第5期34卷 621-625页

作者： shi-yu zhang Teng Fu yue Gong De-Ming Guo Xiu-Li Wang yu-Zhong Wang State Key Laboratory of Polymer Materials Engineering The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric MaterialsNational Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)College of ChemistrySichuan UniversityChengdu 610064China

Ultra-low dielectric loss(Df)and low dielectric constant(Dk)materials are urgently required in highspeed and large-capacity transmission,in which the wholly aromatic liquid crystal polymer(LCP)has gained attention due to its excellent dielectric ***,the relationship between molecular structure and dielectric properties is still not *** this study,two copolyesters containing phenyl or naphthyl structures are synthesized,as well as the effects of benzene and naphthalene mesogens on dielectric properties are *** synthesized copolyesters containing naphthalene structure have good comprehensive properties with high thermal stability(T_(5%)=479℃ and T_g=195-216℃),inherent flame retardance(LOI=33.0-35.0 and UL-94 V-0 level at 0.8 mm),low Dk(2.9-3.0@10 GHz)and low Df(0.0027-0.0047@10 GHz).Naphthalene mesogen can reduce the dielectric loss more significantly than benzene at high frequency by reducing the density and mobility of polarizable groups,which leads to the effectively limited dipole polarization in ***,we proposed a new strategy for designing low Dk and low Df materials.

关键词： Liquid crystal polymer Low dielectric loss Low dielectric constant Naphthalene structure Flame retardant

Donor-acceptor covalent organic frameworks-confined ultrafine bimetallic Pt-based nanoclusters for enhanced photocatalytic H_(2)generation

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Nano Research 2024年第7期17卷 5835-5844页

作者： yu Liu Yawen shi Hua Wang Shengbo zhang Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Key Laboratory for Green Chemical Technology of the Ministry of EducationSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China School of Environmental Science and Engineering Tianjin Key Laboratory of Biomass/Wastes UtilizationTianjin UniversityTianjin 300350China

Photocatalytic hydrogen generation from hydrogen storage media is an effective and promising approach for the green hydrogen industry as well as for achieving carbon neutrality ***,the lower photocatalytic efficiency due to the limited light trapping capacity,low electron transfer rate,and severe aggregation of nanoparticles caused by high surface energy seriously restricts their practical ***,we constructed a series of donor–acceptor(D–A)type covalent organic frameworks to confine ultrafine bimetallic Pt-based nanoclusters for photocatalytic hydrogen generation from ammonia borane(AB)*** visible light irradiation at 20℃,PtCo_(2)@covalent organic framework(COF)showed the highest photocatalytic activity with a turnover frequency(TOF)of 486 min−*** and density functional theory(DFT)calculations reveal that the high catalytic activity is mainly attributed to the strong electronic interactions between D–A type COF and ultrafine PtCo_(2)***,the D–A type COF can significantly enhance the light-trapping ability by fine-tuning the electron-acceptor type in the framework,and accelerate the photogenerated electron transfer from D–A type COF to PtCo_(2)nanocluster,which promotes the adsorption and activation of H_(2)O and AB molecules and accelerates hydrogen ***,PtCo_(2)@COF also exhibited ultra-high durability due to the significantly enhanced resistance to nanocluster aggregation caused by the nanopore confinement effect of D–A type *** believe that this work will provide a theoretical guide for the rational design of efficient D–A COFbased catalysts for photocatalysis.

关键词： light trapping electron transfer donor-acceptor covalent organic frameworks(D-A COFs) bimetallic nanoclusters photocatalysis

Penile metastasis from rectal carcinoma: A case report

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World Journal of Clinical Cases 2022年第19期10卷 6609-6616页

作者： Jun-Jie Sun shi-yu zhang Jun-Jie Tian Bai-Ye Jin Department of Urology The First Affiliated HospitalZhejiang University School of MedicineHangzhou 311000Zhejiang ProvinceChina

BACKGROUND Metastasis to the penis is an unusual event,and penile metastasis from rectal carcinoma(PMRC)is extremely rare and associated with a dismal *** far,approximately 80 cases have been *** SUMMARY Herein,we report the case of a 49-year-old man with *** patient presented to the urology clinic with a complaint of penile pain during *** patient underwent the Dixon operation for rectal carcinoma 2 mo before the *** hospitalisation,abdominal computed tomography revealed a nodular lesion on the left *** postoperative pathological examination revealed a typical intestinal-type *** cases of PMRC were retrieved from PubMed to characterise the clinicopathological features and identify the prognostic factors of *** The analysis suggested that approximately 24 mo is the median time to metastasis occurrence and 150 d is the survival time after ***,poor pathological differentiation,lymph node involvement of the primary RC,metastasis time1 cm,and treatment abandonment are negative predictors of survival *** follow-up,surgical resection,chemotherapy,and radiotherapy may potentially improve the prognosis of patients.

关键词： Rectal carcinoma Penile metastasis Risk factors Prognosis Case report

Cyclodextrin nanofilms with hydrophobic and hydrophilic channels for solvent permeation and molecular sieving

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Nano Research 2024年第7期17卷 6638-6644页

作者： Kai zhang yu Dai Yongli shi Zhaoxin zhang Linji Li Xiaojin zhang Fan Xia Faculty of Materials Science and Chemistry China University of GeosciencesWuhan 430074China Henan Academy of Geology Zhengzhou 450052China

Nanofilms that can fast permeate solvents and accurately sieve molecules are of significant importance for separation.A promising strategy is to align the inner cavities of macrocycles into the channels within nanofilms,and control the channel size by selecting the ***,the channels outside the macrocycles are ***,we prepare nanofilms with hydrophobic channels(cyclodextrin inner cavity)and hydrophilic channels(cyclodextrin outer space)through interfacial polymerization of azobenzene-4,4’-dicarbonyl dichloride and amino-functionalizedβ-*** utilizing the significant geometric changes caused by the photoisomerization of azobenzene,nanofilms with adjustable hydrophilic channel sizes were *** nanofilms have high permeability to polar and non-polar solvents,and can distinguish molecules with almost the same molecular weight but different *** work expands the development of next-generation nanofilms generated through interfacial polymerization by incorporating rational molecular design.

关键词： nanofilm β-cyclodextrin azobenzene interfacial polymerization solvent permeation molecular sieving

Reducing Subspaces of Toeplitz Operators Induced by a Class of Non-analytic Monomials over the Unit Ball

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1767-1777页

作者： Yan yue shi Bo zhang Xu TANG yu Feng LU School of Mathematical Sciences Ocean University of ChinaQingdao 266100P.R.China School of Mathematics and Information Sciences Yantai UniversityYantai 264005P.R.China School of Mathematical Sciences Space Engineering UniversityBeijing 101416P.R.China School of Mathematical Sciences Dalian University of TechnologyDalian 116024P.R.China

In this paper,we describe the minimal reducing subspaces of Toeplitz operators induced by non-analytic monomials on the weighted Bergman spaces and Dirichlet spaces over the unit ball B_(2).It is proved that each minimal reducing subspace M is finite dimensional,and if dim M≥3,then M is induced by a ***,the structure of commutant algebra v(T_(w)N_(z)N):={M^(*)_(w)NM_(z)N,M^(*)_(z)NM_(w)N}′is determined by N and the two dimensional minimal reducing subspaces of(T_(w)N_(z)*** also give some interesting examples.

关键词： Reducing subspace operator-weighted shifts Toeplitz operator von Neumann algebra