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Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： feng Ren Zhuang-Zhuang liang Ming-Xin Niu Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic *** new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

Microstructure,wear and friction behavior of CoCrAITaY-xCNTs composite coatings deposited by laser-induction hybrid cladding

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Rare Metals 2024年第4期43卷 1815-1827页

作者： Sheng-feng Zhou Yu Long Yan-liang Yi Cheng Deng Lian-Xi Hu Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan430074China MOE Key Laboratory of New Processing Technology for Non-Ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsGuangxi UniversityNanning530004China School of Mechatronics Engineering Guangdong Polytechnic Normal UniversityGuangzhou510635China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

To improve the wear performance of CoCrAlYTa coating,part of the carbon nanotubes(CNTs)chemically reacted with Ta to form reinforcement phase(TaC),while the other CNTs were retained as lubrication ***,the CoCrAlYTa-xCNTs(x=0,1,2,and 4;wt%)composite coatings were prepared by laserinduction hybrid cladding(LIHC),and the microstructure and wear resistance of coatings were systematically *** show that the coatings are mainly composed of TaC,y-(Co,Cr)andβ-(Co,Cr)*** the CNTs content increases from 0 wt%to 4 wt%,the volume fraction of TaC increases from 13.11 vol%to 16.12 vol%.Meanwhile,the nano-hardness ofγ-(Co,Cr)andβ-(Co,Cr)Al are improved from 7.49 and 9.72 to 9.36 and 11.19 GPa,*** a result,the microhardness of coating increases from HV536.25 to HV 738.16,the wear rate decreases from32.4×10^(-3)to 6.1×10^(-3)mg·m^(-1),and the average friction coefficient decreases from 0.55 to *** good wear performance of the coating is attributed to the formation of TaC and the existence of remained CNTs lubricant film.

关键词： Carbon nanotube MCrAlY coating Friction and wear performance Laser-induction hybrid cladding

Regulated polarization degree of upconversion luminescence and multiple anti-counterfeit applications

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Rare Metals 2024年第5期43卷 2172-2183页

作者： Dong-Ping Wen Ping Chen Yi liang Xiao-Ming Mo Cao-feng Pan Center On Nanoenergy Research Guangxi Key Laboratory for Relativistic AstrophysicsSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key Laboratory of Micronano Energy and Sensor CAS Center for Excellence in NanoscienceBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100140China

Polarization upconversion luminescence(PUCL)of lanthanide ions(Ln^(3+))has been widely used in single particle tracking,microfluidics detection,three-dimensional displays,and so ***,no effective strategy has been developed for modulating *** we report a strategy to regulate PUCL in Ho^(3+)-doped NaYF4single nanorods based on the number of upconversion *** constructing a multiphoton upconversion system for Ho^(3+),we regulate the degree of polarization(DOP)of PUCL from 0.590 for two-photon luminescence to 0.929 for three-photon upconversion luminescence(UCL).Furthermore,our strategy is verified from cross-relaxation between Ho^(3+)and Yb^(3+),excitation wavelength,excitation power density,and local site *** this regulation strategy of PUCL has also been achieved in Tm^(3+),with the DOP ranging from 0.233 for two-photon luminescence to 0.925 for four-photon UCL Besides,multi-dimensional anti-counterfeiting display has been explored with *** work provides an effective strategy for regulating PUCL and also provides more opportunities for the development of polarization display optical encoding,anti-counterfeiting,and integrated optical devices.

关键词： Polarization upconversion luminescence Degree of polarization Population density of excited state Number of upconversion photons Polarization anti-counterfeitingdisplay

Efficacy and safety of Qingfei Huatan formula in the treatment of acute exacerbation of chronic obstructive pulmonary disease:A multi-centre,randomised,double-blind,placebo-controlled trial

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Journal of Integrative Medicine 2024年第5期22卷 561-569页

作者： Hui-zhi Zhu Cheng-yi Li liang-ji Liu Jia-bing Tong zhi-hui Lan Shu-guang Tian Qiao Li Xiang-li Tong Ji-feng Wu Zhen-gang Zhu Su-yun Li Jian-sheng Li Department of Respiratory Medicine the First Affiliated Hospital of Anhui University of Traditional Chinese MedicineHefei 230031Anhui ProvinceChina Graduate School Anhui University of Traditional Chinese MedicineHefei 230012Anhui ProvinceChina Department of Respiratory Medicine Affiliated Hospital of Jiangxi University of Traditional Chinese MedicineNanchang 330006Jiangxi ProvinceChina Department of Respiratory Diseases the First Affiliated Hospital of Henan University of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina Department of Pulmonary Diseases Taihe Hospital of Traditional Chinese Medicine Affiliated to Anhui University of Traditional Chinese MedicineFuyang 236600Anhui ProvinceChina Department of Respiratory and Critical Care Medicine Jiangxi Province Hospital of Integrated Chinese and Western MedicineNanchang 330002Jiangxi ProvinceChina Department of Respiratory Medicine the First Affiliated Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300381China Collaborative Innovation Center for Respiratory Disease Diagnosis and Treatment and Chinese Medicine Development of Henan Province Zhengzhou 450046Henan ProvinceChina

Background Chronic obstructive pulmonary disease(COPD),a common respiratory disease,can be effectively treated by traditional Chinese medicine(TCM).Qingfei Huatan,a TCM formula,has been reported to effectively alleviate the clinical symptoms of COPD ***,there is a lack of multi-centre,randomised,double-blind,controlled clinical trials documenting the clinical efficacy and safety of this formula in the treatment of acute exacerbation of COPD(AECOPD).Objective This study evaluated the efficacy and safety of Qingfei Huatan formula in the treatment of AECOPD,thereby providing high-quality clinical ***,setting,participants and interventions A total of 276 patients with AECOPD were included in this multi-centre,randomised,double-blind,placebo-controlled trial and were randomised into treatment and control groups at a ratio of 1:*** in the treatment and control groups took Qingfei Huatan granules or simulated Qingfei Huatan granules twice a day,for 14 days,in addition to Western medicine *** patients were followed up for 3 *** outcome measures The primary outcome was time taken to symptom *** secondary outcomes included duration of antibiotic use,clinical symptom and sign score,TCM syndrome score,dyspnoea score,and quality of life(QOL)***,the safety of the formula was assessed through routine urine and stool tests,electrocardiograms,liver and kidney function tests,and the observation of adverse events throughout the *** The time taken for effective stabilisation(P<0.05)and obvious stabilisation(P<0.01),and the duration of antibiotic use(P<0.05)were significantly shorter in the treatment group than in the control *** days 6,9,12 and 14 of treatment,clinical symptom and sign score decreased in both groups,particularly in the treatment group(P<0.01).On days 9,12 and 14 of treatment,the TCM syndrome scores of both groups were reduced(P<0.01),with more significant reductions in the treatm

关键词： Acute exacerbation of chronic obstructive pulmonary disease Clinical trial Syndrome of phlegm-heat congesting lung Qingfei Huatan formula Traditional Chinese medicine

In-situ deposited anti-aging TiN capping layer for Nb superconducting quantum circuits

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Chinese Physics B 2024年第9期33卷 133-137页

作者： Hao-Ran Tao Lei Du liang-liang Guo Yong Chen Hai-feng Zhang Xiao-Yan Yang Guo-liang Xu Chi Zhang zhi-Long Jia Peng Duan Guo-Ping Guo CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Origin Quantum Computing Company Limited Hefei 230088China

The performance of Nb superconducting quantum devices is predominantly limited by dielectric loss at the metal–air interface,where Nb2O5 is considered the main loss ***,we suppress the formation of native oxides by in-situ deposition of a TiN capping layer on the Nb *** TiN capping layers,no Nb2O5 forms on the surface of the Nb *** quality factor Qi of the Nb resonator increases from 5.6×10^(5) to 7.9×10^(5) at low input power and from 6.8×10^(6) to 1.1×10^(7)at high input ***,the TiN capping layer also shows good aging resistance in Nb resonator devices,with no significant performance fluctuations after one month of *** findings highlight the effectiveness of TiN capping layers in enhancing the performance and longevity of Nb superconducting quantum devices.

关键词： anti-aging oxidation dielectric loss Nb superconducting quantum circuits

High performance photodegradation resistant PVA@TiO_(2)/carboxyl-PES self-healing reactive ultrafiltration membrane

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Chinese Journal of Chemical Engineering 2024年第2期66卷 31-39页

作者： Yu liang Yuanfang Fan Zhongmin Su Mingxin Huo Xia Yang Hongliang Huo Chi Wang zhi Geng College of Environment Engineering Research Center of Low-Carbon Treatment and Green Development of Polluted Water in Northeast ChinaMinistry of EducationNortheast Normal UniversityChangchun 130117China School of Science Hainan UniversityHaikou 570225China

The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF *** self-cleaning UF membranes can effectively alleviate the problem of membrane ***,the self-cleaning process may accelerate membrane *** these concerns,we present an innovative design concept for composite self-healing materials based on self-cleaning UF *** begin,TiO_(2)nanoparticles were incorporated into the polymer molecular structure via molecular design,resulting in the synthesis of TiO_(2)/carboxyl-polyether sulfone(PES)hybrid ***,the nonsolvent-induced phase inversion technique was employed to prepare a novel of UF ***,a polyvinyl alcohol(PVA)hydrogel coating was applied to the hybrid UF membrane surface to create PVA@TiO_(2)/carboxyl-PES self-healing reactive UF *** establishing a covalent bond,the TiO_(2)nanoparticles were effectively and uniformly dispersed within the UF membrane,leading to exceptional self-cleaning ***,the water-absorbing and swelling properties of PVA hydrogel,along with its capacity to form hydrogen bonds with water molecules,resulted in UF membranes with improved hydrophilicity and active self-healing *** results demonstrated that the water contact angle of PVA@5%TiO_(2)/carboxyl-PES UF membrane was 43.1°.Following a 1-h exposure to simulated solar exposure,the water flux recovery ratio increased from 48.16%to 81.03%.Moreover,even after undergoing five cycles of 12-h simulated sunlight exposure,the UF membranes exhibited a consistent retention rate of over 97%,thus fully demonstrating their exceptional self-cleaning,antifouling,and selfhealing *** anticipate that the self-healing reactive UF membrane system will serve as a pioneering and comprehensive solution for the self-cleaning antifouling challenges encountered in UF membranes while also effectively mitigating the aging effects of reactive

关键词： Ultrafiltration membrane Self-cleaning Self-healing Poly(aryl ether sulfone)

A model for predicting the segregation directions of binary Geldart B particle mixtures in bubbling fluidized beds

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Particuology 2024年第7期90卷 340-349页

作者： Chenmin Liu Yuemin Zhao Yanjiao Li Yuqing feng Chenlong Duan Chenyang Zhou liang Dong Key Laboratory of Coal Processing and Efficient Utilization Ministry of EducationChina University of Mining and TechnologyXuzhou221116China School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou221116China Mineral Resources Business Unit CSIROClaytonVIC 3169Australia

In gas fluidization processes involving different types of particles,the mixing or segregation behavior of the solid mixture is crucial to the overall outcome of the *** study develops a model to predict the segregation directions of binary mixtures of Geldart B particles with density and size differences in bubbling fluidized *** proposed model was established by combining the particle segregation model,a previous particle segregation model,with a derived bed voidage equation of the bubbling fluidization based on the two-phase *** model was then analyzed with different function graphs of the model equations under various *** results indicated that an increase in gas velocity or volume fraction of larger particles would strengthen size segregation,causing the larger and less dense components to *** validate the model,42 sets of data collected from 6 independent literature sources were compared with the predictions of the *** the gas velocities were below 3.2 times the minimum gas velocity,the predictions were consistent with experimental *** study has shed new light on the mechanisms of particle segregation in binary fluidized systems and provides a theoretical foundation for designing and manipulating gas-solid fluidized reactors.

关键词： Particle segregation Binary mixture Bubbling fluidization Geldart B particles Two-phase theory

Roles of nanoparticles in arsenic mobility and microbial community composition in arsenic-enriched soils

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Journal of Environmental Sciences 2024年第4期138卷 301-311页

作者： Ting Luo Qining Zheng Jie Yu Weihao liang Yan Sun Guixiang Quan feng Zhou School of Environmental Science and Engineering Yancheng Institute of TechnologyYancheng 224051China Jiangsu Provincial Key Laboratory of Coastal Ecology and Pollution Control Yancheng 224051China School ofEnvironment and Civil Engineering Jiangnan UniversityWuxi 214122China

Environmental effects of nano remediation engineering of arsenic(As)pollution need to be *** this study,the roles of Fe_(2)O_(3)and TiO_(2)nanoparticles(NPs)on the microbial mediated As mobilization from As contaminated soil were *** addition of Fe_(2)O_(3)and TiO_(2)NPs restrained As(V)release,and stimulated As(Ⅲ)***(V)concentration decreased by 94% and 93% after Fe_(2)O_(3)addition,and decreased by 89% and 45% after Ti O_(2)addition compared to the Biotic and Biotic+Acetate(amended with sodium acetate)controls,*** maximum values of As(Ⅲ)were 20.5 and 27.1μg/L at 48 d after Fe_(2)O_(3)and TiO_(2)NPs addition,respectively,and were higher than that in Biotic+Acetate control(12.9μg/L).The released As co-precipitated with Fe in soils in the presence of Fe_(2)O_(3)NPs,but adsorbed on TiO_(2)NPs in the presence of TiO_(2)***,the addition of NPs amended with sodium acetate as the electron donor clearly promoted As(V)reduction induced by *** NPs addition changed the relative abundance of soil bacterial community,while Proteobacteria(42.8%-70.4%),Planctomycetes(2.6%-14.3%),and Firmicutes(3.5%-25.4%)were the dominant microorganisms in *** potential As/Fe reducing bacteria were related to Pseudomonas,Geobacter,Desulfuromonas,and *** addition of Fe_(2)O_(3)and TiO_(2)NPs induced to the decrease of arr A *** results indicated that the addition of NPs had a negative impact on soil microbial population in a long *** findings offer a relatively comprehensive assessment of Fe_(2)O_(3)and TiO_(2)NPs effects on As mobilization and soil bacterial communities.

关键词： Fe_(2)O_(3)and TiO_(2)nanoparticles Arsenic reduction Mobilization Functional gene Microbial community

InSAR-derived surface deformation characteristics and mining subsidence parameters in mountain coal mines

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Journal of Mountain Science 2024年第9期21卷 3139-3156页

作者： JIANG Xiaowei SHI Wenbing liang feng GUI Jingjing LI Jiawei Key Laboratory of Karst Georesources and Environment Ministry of EducationGuizhou UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Mountain Geohazard Prevention R&D Center of Guizhou Province Guiyang 550025China

Mining-induced surface deformation disrupts ecological balance and impedes economic *** study employs SBAS-InSAR with 107-view of ascending and descending SAR data from Sentinel-1,spanning February 2017 to September 2020,to monitor surface deformation in the Fa’er Coal Mine,Guizhou *** on the surface deformation time series reveals the relationship between underground mining and surface *** geological conditions,mining activities,duration,and ranges,the study determines surface movement parameters for the coal *** asserts that mining depth significantly influences surface movement parameters in mountainous mining *** mining depth elevates the strike movement angle on the deeper side of the burial depth by 22.84°,while decreasing by 7.74°on the shallower *** movement angles decrease by 4.06°,while downhill movement angles increase by 15.71°.This emphasizes the technology's suitability for local mining design,which lays the groundwork for resource development,disaster prevention,and ecological protection in analogous contexts.

关键词： Time-series InSAR Surface deformation Subsurface mining Mining subsidence