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Frontiers in Energy 2024年第4期18卷 525-534页

作者： Juntian niu Shengzhuo chen Xianrong ZHENG Haiyu LIU Yan jiN jingyu RAN College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Low-grade Energy Utilization Technologies and Systems(Ministry of Education) Chongqing UniversityChongqing 400044China

In recent years,the dry reforming of methane(DRM)reaction has gained widespread attention due to its effective utilization of two major greenhouse *** Ni-based catalysts for DRM exhibit a strong dependence on particle size,however,the reaction mechanisms involved remain *** this work,the effect of metal particle size on CO_(2)activation and CO formation was explored in the DRM reaction using the density functional ***/MgO(x=13,25,37)was constructed to investigate the CO_(2)activation and the formation of CO during the DRM *** is found that CO_(2)is more inclined to undergo chemisorption on Nix/MgO before *** the variation in particle size,the main activation pathway of CO_(2)on the catalyst *** the smallest Ni13/MgO,CO_(2)tends to directly dissociate,while on the larger Ni25/MgO and Ni37/MgO,the hydrogenation dissociation of CO_(2)is more kinetically *** to Ni13/MgO and Ni37/MgO,the oxidation of surface C atoms and the oxidation of CH occur more readily on Ni25/*** indicates that C atoms are less likely to form on Ni25 particle and are more easily to be *** some extent,the results suggest that Ni25/MgO exhibits superior resistance to carbon formation.

关键词： particle size Ni/MgO catalyst CO_(2)activation CO formation

Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates

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Chinese Journal of Polymer Science 2024年第3期42卷 292-298,I0005页

作者： Hao-Tian Zhang Ming-Xin niu Qi Zhang chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Materials Science and Engineering Jilin UniversityChangchun 130025China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics.

关键词： Polyisothioureas Alternative copolymer Aziridines Isothiocayanates

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

Regenerative treatment of ophthalmic diseases with stem cells:Principles,progress,and challenges

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Advances in Ophthalmology Practice and Research 2024年第2期4卷 52-64页

作者： Yifei niu Junfeng ji Ke Yao Qiuli Fu Eye Center of the Second Affiliated Hospital Zhejiang University School of MedicineHangzhouZhejiang ProvinceChina Zhejiang Provincial Key Lab of Ophthalmology HangzhouZhejiang ProvinceChina Center of Stem Cell and Regenerative Medicine School of MedicineZhejiang UniversityHangzhouZhejiang ProvinceChina Zhejiang Provincial Key Laboratory of Tissue Engineering and Regenerative Medicine HangzhouChina

Background:Degenerate eye disorders,such as glaucoma,cataracts and age-related macular degeneration(AMD),are prevalent causes of blindness and visual impairment *** eye disorders,including limbal stem cell deficiency(LSCD),dry eye diseases(DED),and retinitis pigmentosa(RP),result in symptoms such as ocular discomfort and impaired visual function,significantly impacting quality of *** therapies are limited,primarily focus on delaying disease progression,while emerging stem cell therapy directly targets ocular tissues,aiming to restore ocular function by reconstructing ocular *** text:The utilization of stem cells for the treatment of diverse degenerative ocular diseases is becoming increasingly significant,owing to the regenerative and malleable properties of stem cells and their functional ***,stem cell therapy for ophthalmopathy involves various cell types,such as embryonic stem cells(ESCs),induced pluripotent stem cells(iPSCs),mesenchymal stem cells(MSCs),and retinal progenitor cells(RPCs).In the current article,we will review the current progress regarding the utilization of stem cells for the regeneration of ocular tissue covering key eye tissues from the cornea to the *** therapies aim to address the loss of functional cells,restore damaged ocular tissue and or in a paracrine-mediated *** also provide an overview of the ocular disorders that stem cell therapy is targeting,as well as the difficulties and opportunities in this ***:Stem cells can not only promote tissue regeneration but also release exosomes to mitigate inflam-mation and provide neuroprotection,making stem cell therapy emerge as a promising approach for treating a wide range of eye disorders through multiple mechanisms.

关键词： Stem cell Ocular diseases Induced pluripotent stem cells Mesenchymal stem cells Cataracts Glaucoma Diabetic retinopathy Retinal degenerative diseases

Recent progress of self-supported air electrodes for flexible Zn-air batteries

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Journal of Energy Chemistry 2024年第2期89卷 110-136,I0004页

作者： chen Xu Yanli niu Vonika Ka-Man Au Shuaiqi Gong Xuan Liu jianying Wang Deli Wu Zuofeng chen School of Chemical Science and Engineering Tongji UniversityShanghai 200092China College of Environmental Science&Engineering Tongji UniversityShanghai 200092China Department of Science and Environmental Studies The Education University of Hong KongHong KongChina

Smart wearable devices are regarded to be the next prevailing technology product after smartphones and smart homes,and thus there has recently been rapid development in flexible electronic energy storage *** them,flexible solid-state zinc-air batteries have received widespread attention because of their high energy density,good safety,and *** bifunctional oxygen electrocatalysts are the primary consideration in the development of flexible solid-state zinc-air batteries,and self-supported air cathodes are strong candidates because of their advantages including simplified fabrication process,reduced interfacial resistance,accelerated electron transfer,and good *** review outlines the research progress in the design and construction of nanoarray bifunctional oxygen *** from the configuration and basic principles of zinc-air batteries and the strategies for the design of bifunctional oxygen electrocatalysts,a detailed discussion of self-supported air cathodes on carbon and metal substrates and their uses in flexible zinc-air batteries will ***,the challenges and opportunities in the development of flexible zinc-air batteries will be discussed.

关键词： Bifunctional electrocatalysts Oxygen reduction reaction Oxygen evolution reaction Self-supported air electrodes Flexible zinc-air batteries

Design,Simulation and Kinematic Validation of a Hip Prosthetic Mechanism with a Multimotor Function

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Journal of Bionic Engineering 2024年第3期21卷 1321-1333页

作者： Majun Song Zhongyi Li jingjing jiang Weihai chen Sheng Guo Hao Zheng Lianzheng niu Hangzhou Innovation Institute Beihang UniversityHangzhou310051China Hangzhou Huacheng Software Technology Co.Ltd. Hangzhou310051China School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing100044China

We previously developed a powered hip prosthetic mechanism with kinematic functions of hip flexion-extension and abduction-adduction,and its theoretical and simulation-based kinematics were *** internal-external hip rotation has a positive effect on the movements of human lower limbs according to medical research,we developed a novel hip prosthetic mechanism based on a previous hip prosthesis that possesses motion characteristics similar to those of a human bionic hip,and the motion characteristics of multiple Degrees-of-Freedom(DoFs)were analyzed after kinematic ***,a walking model of the human‒machine model was established,and the walking stability of an amputee,which reflects the rehabilitation effect,was explored while the hip prosthetic mechanism considered the internal-external rotation of the ***,a prototype and its verification platform were built,and kinematic validation of the hip prosthetic mechanism was carried *** results showed that the designed Parallel Mechanism(PM)possesses human-like motion characteristics similar to those of a human bionic hip and can be used as a hip ***,the existing motion characteristic of internal-external hip rotation can enhance the walking stability of an amputee via this hip prosthetic mechanism.

关键词： Hip prosthetic mechanism Parallel mechanism Walking stability Kinematic validation

High adsorption selectivity of activated carbon and carbon molecular sieve boosting CO_(2)/N_(2) and CH_(4)/N_(2) separation

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Chinese Journal of Chemical Engineering 2024年第3期67卷 282-297页

作者： Siang chen Wenling Wu Zhaoyang niu Deqi Kong Wenbin Li Zhongli Tang Donghui Zhang The Research Center of Chemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Flue gas and coal bed methane are two important sources of greenhouse *** swing adsorption process has a wide range of application in the field of gas separation,and the selection of adsorbent is *** this regard,in order to assess the better adsorbent for separating CO_(2) from flue gas and CH_(4) from coal bed methane,adsorption isotherms of CO_(2),CH_(4) and N_(2) on activated carbon and carbon molecular sieve are measured at 303.15,318.15 and 333.15 K,and up to 250 *** experimental data fit better with Langmuir 2 compared to Langmuir 3 and Langmuir-Freundlich models,and Clausius-Clapeyron equation was used to calculate the isosteric *** the order of the adsorbed amount and the adsorption heat on the two adsorbents are CO_(2)>CH_(4)>N_(2).The adsorption kinetics are calculated by the pseudo-first kinetic model,and the order of adsorption rates on activated carbon is N_(2)-CH_(4)>CO_(2),while on carbon molecular sieve,it is CO_(2)-N_(2)>CH_(4).It is shown that relative molecular mass and adsorption heat are the primary effect on kinetics for activated carbon,while kinetic diameter is the main resistance factor for carbon molecular ***,the adsorption selectivity of CH_(4)/N_(2) and CO_(2)/N_(2) were estimated with the ideal adsorption solution theory,and carbon molecular sieve performed best at 318.15 K for both CO_(2) and CH_(4) *** study suggested that activated carbon is a better choice for separating flue gas and carbon molecular sieve can be a strong candidate for separating coal bed methane.

关键词： Activated carbon Carbon molecular sieve Adsorbent evaluation Adsorption equilibrium and kinetics Heat of adsorption Selectivity

Nonlinear proinflammatory effect of short-term PM_(2.5)exposure:A potential role of lipopolysaccharide

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Journal of Environmental Sciences 2024年第2期136卷 292-300页

作者： Fangxia Shen Mutong niu Haoxuan chen Ting Zhang jing Li Haijie Tong Yan Wu School of Space and Environment Beihang UniversityBeijing 100191China College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China Institute of Surface Science Helmholtz-Zentrum HereonGeesthacht 21502Germany School of Environmental Science and Engineering Shandong UniversityJinan 250100China

The association between PM_(2.5)(particulate matter≤2.5μm)short-term exposure and its health effect is non-linear from the epidemiological *** this nonlinearity is suggested to be related with the PM_(2.5)heterogeneity,however,the underlying biological mechanism is still ***,a total of 38 PM_(2.5)filters were collected continuously for three weeks in winter Beijing,with the ambient PM_(2.5)varying between 10 and 270μg/m^(3).Human monocytes-derived macrophages(THP-1)were treated with PM_(2.5)water-soluble elutes at10μg/mL to investigate the PM_(2.5)short-term exposure effect from a proinflammatory *** proinflammatory cytokine tumor necrosis factor(TNF)induced by the PM_(2.5)elutes at equal concentrations were unequal,showing the heterogeneity of PM_(2.5)proinflammatory *** the various chemical and biological components,lipopolysaccharide(LPS)showed a strong positive association with the TNF ***,some outliers were observed among the TNF-LPS ***,for PM_(2.5)from relatively clean air episodes,the higher LPS amount corresponded to relatively low TNF *** this phenomenon was also observed in the promotion tests by treating macrophages with PM_(2.5)elutes dosed with additional trace *** expression analysis indicated the involvement of oxidative-stress related genes in the LPS signaling ***,a potential oxidative-stress-mediated suppression on the PM_(2.5)-borne LPS proinflammatory effect was proposed to be accounted for the ***,the results showed the differential role of LPS in the heterogeneity of PM_(2.5)proinflammatory effects from a component-based *** experimental studies are needed to elucidate the signaling pathway of LPS attached on PM_(2.5)from different air quality episodes.

关键词： Fine PM PM_(2.5)pro-inflammatory effects Aerosol health effect Endotoxin Oxidative stress

pH-sensitive KHA/CMC-Fe^(3+)@CS hydrogel loading and the drug release properties of riboflavin

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Particuology 2024年第3期86卷 13-23页

作者： jie Song Xi Li Yuhua niu Lijun chen Zhiqiang Wei Yidan Li Youqian Wang Shaanxi University of Science&Technology Xi'an710021China

To improve drug utilization,reduce the drug administration frequency,increase the release time,and reduce the drug side effects in the human body,we prepared(KHA/CMC-Fe^(3+))@CS hydrogel spheres using green and natural potassium humate(KHA),carboxymethyl cellulose(CMC),and chitosan(CS)as raw materials and Fe3+as a crosslinking agent,and loaded them with riboflavin for drug sustainedrelease study using the drop ball *** tests with FTIR,SEM,TG,and X-ray diffractometer showed that the coordination among KHA,CMC,and Fe^(3+)formed a three-dimensional network structure,where cs was encapsulated on the surface of the hydrogel spheres via noncovalent bonding,resulting in good thermal *** stability,drug loading,swelling,and in vitro release of the(KHA/CMC-Fe^(3+))@CS hydrogel spheres were *** results showed that the hydrogel spheres were significantly pH-sensitive,with 11.16 g/g higher swelling in an alkaline environment(pH=7.4)than that in an acidic environment(pH=1.2).The swelling and drug release process of the hydrogel spheres were analyzed using mathematical models,concluding that the hydrogel swelling follows Schott second-order swelling kinetics,and the drug release mechanism was Fickian delivery mode.

关键词： Potassium humate Hydrogel spheres pH-sensitive Drugsustained-release Drug release model

Long-term in vivo chimeric cells tracking in non-human primate

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Protein & Cell 2024年第3期15卷 207-222页

作者： Junmo Wu Yu Kang Xiang Luo Shaoxing Dai Yuxi Shi Zhuoyao Li Zengli Tang Zhenzhen chen Ran Zhu Pengpeng Yang Zifan Li Hong Wang Xinglong chen Ziyi Zhao Weizhi ji Yuyu niu State Key Laboratory of Primate Biomedical Research Institute of Primate Translational MedicineKunming University of Science and TechnologyKunming 650500China Yunnan Key Laboratory of Primate Biomedical Research Kunming 650500China Faculty of Life Science and Technology Kunming University of Science and TechnologyKunming 650500China

Non-human primates(NHPs)are increasingly used in preclinical trials to test the safety and efficacy of biotech-nology ***,given the ethical issues and costs associated with this model,it would be highly advantageous to use NHP cellular models in clinical ***,developing and maintaining the naive state of primate pluripotent stem cells(PSCs)remains difficult as does in vivo detection of PSCs,thus limiting biotech-nology application in the cynomolgus ***,we report a chemically defined,xeno-free culture system for culturing and deriving monkey PSCs in *** cells display global gene expression and genome-wide hypometh-ylation patterns distinct from monkey-primed *** also found expression of signaling pathways components that may increase the potential for chimera *** for biomedical applications,we were also able to integrate bioluminescent reporter genes into monkey PsCs and track them in chimeric embryos in vivo and in *** engineered cells retained embryonic and extra-embryonic developmental ***,we generated a chimeric monkey carrying bioluminescent cells,which were able to track chimeric cells for more than 2 years in living *** study could have broad utility in primate stem cell engineering and in utilizing chimeric monkey models forclinical studies.

关键词： pluripotent stem cells bioluminescence imaging non-human primates