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Journal of Rare Earths 2022年第12期40卷 1920-1926,I0004页

作者： Min Xie Shengli An Xiwen Song Jinxiao Bao fen zhou School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010China Inner Mongolia Key Laboratory of Advanced Ceramic Materials and Devices Baotou 014010China

Rare earth Er^(3+)doped(Sm_(1-x)Er_(x))_(2)Zr_(2)O_(7)(x=0.1,0.2,and 0.3)ceramic samples were synthesized using a solid state reaction *** microstructure and thermal properties of these ceramics were investigated to evaluate their potential as thermal barrier coating *** results show that ceramics are compact with regular-shaped grains of 1-5μm size.(Sm_(1-x)Er_(x))_(2)Zr_(2)O_(7)has a pyrochlore structure mainly determined by ionic radius ratio,but the ordering degree decreases with increase of the Er_(2)O_(3)*** is no phase transformation from 1000 to 1200℃,and the(Sm_(1-x)Er_(x))_(2)Zr_(2)O_(7)ceramics exhibit excellent phase stability during thermal treatment at 1200℃for 100 h and 1400℃for 50 *** thermal conductivities of dense(Sm_(1-x)Er_(x))_(2)Zr_(2)O_(7)ceramics range from 1.52 to 1.59 W/(m·K),which is lower than that of Sm_(2)Zr_(2)O_(7),and decrease as the Er2O3content ***,the thermal expansion coefficient of(Sm_(1-x)Er_(x))_(2)Zr_(2)O_(7)is higher than that of Sm_(2)Zr_(2)O_(7).

关键词： (Sm_(1-x)Er_(x))_(2)Zr_(2)O_(7) Pyrochlore structure Thermal-physical properties Er^(3+)doping Rare earths

Influence of pore size optimization in catalyst layer on the mechanism of oxygen transport resistance in PEMFCs

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Progress in Natural Science:Materials International 2020年第6期30卷 839-845页

作者： Shumeng Guan fen zhou Jinting Tan Mu Pan State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Hubei Provincial Key Laboratory of Fuel Cells Wuhan University of Technology

In PEMFC, the oxygen transport resistance severely hinders the cell from achieving high performance. In this paper, pore-forming agent was used to optimize the pore size distribution of the catalyst layer(CL), and to study its effect on the mechanism of oxygen transport resistance, including molecular diffusion resistance, Knudsen diffusion resistance, and local O2resistance in CL. The results showed that with the pore formation the cell performance had a significant improvement at high current density, mainly due to its better oxygen transport properties, especially under low platinum conditions. The addition of pore-forming agent moved the pore diameter toward a larger pore diameter with a range from 70 to 100 nm, and also obtaining a higher cumulative pore volume. It was found that the increase of the cumulative pore volume and larger pore size were conducive to the diffusion of oxygen molecules in CL, and the resistance caused by which was the dominant part in total transport resistance. Further tests indicated that the improvement of molecular diffusion resistance was much larger than that of Knudsen diffusion resistance in the catalyst layer after pore formed. In addition, the optimized pore structure will also get a higher number of effective pores, which resulted in an increased effective area of the ionomer on the Pt surface. The higher effective area of the ionomer was particularly beneficial for the reduction of local O2resistance with low Pt loading.

关键词： Pore size optimization Pore-forming agent Oxygen transport resistance PEMFC

Substituent Influence of Yttria by Gadolinia on the Tetragonal Phase Stability for Y_2O_3-Ta_2O_5-ZrO_2 Ceramics at 1300℃

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Journal of Materials Science & Technology 2014年第4期30卷 381-386页

作者： Xiaoqing Niu Min Xie fen zhou Rende Mu Xiwen Song Shengli An Inner Mongolia Key Laboratory of Advanced Ceramics and Device School of Materials and MetallurgyInner Mongolia University of Science and Technology Beijing Institute of Aeronautical Materials

The influences of equimolar substitution of yttria by gadolinia on the phase constituent and stability for Y203- Ta2Os-Zr02 ceramics have been investigated. The ceramics with the Gd content lower than 8 tool% exhibit pure tetragonal phase as well as high tetragonal phase stability. However, the high Gd containing ceramics consist of t-Zr02, m-Zr02 and monoclinic GdTa04 and show complicated phase evolution behaviors. The fractions of monoclinic Zr02 and GdTa04 increase with increasing Gd content, indicating that the excessive substitution of Gd for Y results in a reduction in the tetragonal phase stability. In addition, the lower Gd containing ceramics show an almost invariable tetragonality, while the higher Gd containing ceramics reveal a composition-dependent tetragonality. Accordingly, an association of the tetragonal phase stability and tetragonality with the Gd concentration is established, which provides us a clue to understand the phase stability of these ceramics.

关键词： Ceramics Zr02 X-ray diffraction Thermal stability

Synthesis and Characterization of Lignin Grafting Modification-based Aliphatic Superplasticizer

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Journal of Wuhan University of Technology(Materials Science) 2018年第3期33卷 661-668页

作者：马双平丁庆军 zhou fen ZHU Huaxiong School of Materials Science and Engineering Wuhan University of Technology Wuhan Subo New Building Materials Co. Ltd.

Lignin as the main component of black liquor is generally employed to modify aliphatic superplasticizer（AFS）. However, the modification effect is hard to evaluate correctly due to the uncertain molecular structure of lignin and the disturbance from the complexity of black liquor compositions. In this paper, the purified lignin via acid precipitation from straw black liquor is used to modify AFS. The modified AFS named as LAFS for short presents lower molecular mass than AFS. It is assumed that it is due to the single active site of guaiacol segments in lignin by which lignin graft modifies AFS in virtue of methylolation reaction. In order to verify this assumption, guaiacol and dihydro eugenol as the typical segments of lignin macromolecule were selected, respectively, as the simplified model compounds of lignin to modify AFS, and corresponding products are abbreviated in GAFS and DAFS. Both GAFS and DAFS show the lower molecular mass than unmodified AFS. FTIR and TG-DTG analyses prove that lignin is successfully grafted onto AFS. The graft modification of lignin results in a decrease in electrostatic epulsion, but an enhanced steric hindrance. Therefore, although the replacement rate of lignin in LAFS was about 23.3%, the dispersion performance was only slightly affected.

关键词： grafting modification lignin aliphatic superplasticizer model compound dispersion performance

Analysis of both chitinase and chitosanase produced by Sphingomonas ***-5

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第11期8卷 831-838页

作者： ZHU Xu-fen zhou Ying fenG Jun-li College of Life Science Zhejiang University Hangzhou 310058 China

A novel chitinolytic and chitosanolytic bacterium, Sphingomonas sp. CJ-5, has been isolated and characterized. It secretes both chitinase and chitosanase into surrounding medium in response to chitin or chitosan induction. To characterize the enzymes, both chitinase and chitosanase were purified by ammonium sulfate precipitation, Sephadex G-200 gel filtration and DEAE-Sepharose Fast Flow. SDS-PAGE analysis demonstrated molecular masses of chitinase and chitosanase were 230 kDa and 45 kDa respectively. The optimum hydrolysis conditions for chitinase were about pH 7.0 and 36 ℃, and these for chitosanase were pH 6.5 and 56 ℃, respectively. Both enzymes were quite stable up to 45 ℃ for one hour at pH 5-8. These results show that CJ-5 may have potential for industrial application particularly in recycling of chitin wastes.

关键词： Sphingomonas sp. Chitinase Chitosanase

Chinese Herbal Medicine in Treatment of Polyhydramnios:a Meta-analysis and Systematic Review

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Chinese Medical Sciences Journal 2013年第2期28卷 72-81页

作者： fen zhou Yu-fang Hao Yan Chen Tong Wang Nursing School Beijing University of Chinese Medicine

Objective To compare the efficacy of Chinese herbal medicine （therapy A） or Chinese herbal medicine plus indomethacin （therapy B） with that of indomethacin alone （therapy C） in treating polyhydramnios. Methods Literatures published up to April 2012 were retrieved from PubMed, Embase and Cochrane library, Chinese National Knowledge Infrastructure （CNKI）, Chinese Scientific and Technological Periodical Database （VIP）, Wangfang, and Traditional Chinese Medicine online. Two researchers collected data independently. The assessment of methodological quality was based on Cochrane handbook and the materials were analyzed with software RevMan 5.1.2. The outcome measure index was relative risk or difference of mean value （95% confidence interval）. The following outcomes were evaluated：（1） general clinical improvement rate; （2） maximum vertical pocket depth; （3） amniotic fluid index （AH） value; （4） rate of fetal ductus arteriosus constriction; （5） incidence of adverse events. Results Based on the search strategy, 5 trails involving 1017 patients were finally included. Compared with therapy C, therapy A decreased the rate of fetal ductus arteriosus constriction （P〈0.01）. Therapy B was more effective than therapy C in general clinical improvement and decrease of AH for polyhydramnios （P〈 0.01 ）. No serious adverse events were reported in therapy A and therapy B. Conclusions Compared with therapy C, therapy A and therapy B may appear to be more effective for polyhydramnios. However, the exact effect needs to be confirmed with well-designed large-scale clinical trials.

关键词： Chinese herbal medicine polyhydramnios meta-analysis systematic review

Acupoint Herbal Patching with or without Conventional Treatment for Stable Chronic Obstructive Pulmonary Disease: a Systematic Review of Randomized Controlled Trials

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World Journal of Traditional Chinese Medicine 2015年第1期1卷 45-58页

作者： fen zhou Ya-Wei Shan George Lewith Jian-Ping Liu Centre for Evidence-Based Chinese Medicine Beijing University of Chinese Medicine Nursing School Beijing University of Chinese Medicine University of Southampton

Background: Acupoint herbal patching(AHP) alone or as an adjuvant therapy with conventional treatment(CT) has been widely used for prevention and treatment of chronic obstructive pulmonary disease(COPD). However, current clinical evidence from a systematic review of RCTs is ***: To evaluate the effectiveness and safety of AHP with or without CT for people with COPD at stable ***: We searched randomized controlled trials comparing AHP(with or without CT) with no intervention, placebo, or CT from six databases. Two authors selected studies, extracted data and evaluated risk of bias of included trials. Rev Man 5.2 software was used to analysis ***: Twenty one RCTs(2327 participants) were included. AHP of non sanfu applied on no fixed dates with CT significantly decreased the mean frequency of acute exacerbation of COPD(times per year)(MD:-1.24; 95% CI:-2.02 to-0.46; 2 trials), and improved lung function parameters and quality of life. The AHP with CT showed no better effect in 6-minute walking distance(6 MWD) that CT alone. AHP applied at sanfu(specific dates based on lunar calendar) with CT had significant effect for 6 MWD(MD: 11.20; 95% CI: 0.83 to 21.56; I^2= 0%;3 trials). One trial reported skin irritation from AHP. Another trial reported two patients had eye discomfort, which was inferred as the adverse effects of ***: AHP used as an adjunct to CT, appears to be more effective than CT alone in patients with stable COPD. However, further large,rigorously designed trials are warranted to confirm these potential effects.

关键词： Traditional chinese medicine Acupoint herbal patching Chronic obstructive pulmonary disease Treatment Systematic review Randomized controlled trials

Synthesis and biological evaluation of 2,4-diaminopteridine derivatives as nitric oxide synthase inhibitor

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Chinese Chemical Letters 2009年第4期20卷 420-422页

作者： Fei Ma Gang Lu Wei fen zhou Qiu Juan Wang Yi Hua Zhang Qi Zheng Yao School of Pharmacy China Pharmaceutical University Nanjing 210009 China

A series of novel 2,4-diamino-pteridines （9a-l） were synthesized and evaluated as inhibitors of inducible nitric oxide synthase （iNOS） in vitro. It was found that 9a, 9d, 9e, 9h, 9i and 91 showed potent inhibitory activities similar to that of methotrexate （MTX）, while the activities of 9b, 9c, 9f, 9g, 9j and 9k are stronger than MTX.

关键词： Nitric oxide Tetrahydrobiopterin Nitric oxide synthase Synthesis Inhibitive activity

Short-term effectiveness of intelligent navigated laser photocoagulation versus subthreshold micropulse laser in patients with chronic central serous chorioretinopathy

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International Journal of Ophthalmology(English edition) 2024年第11期17卷 2045-2051页

作者： fen zhou Cheng-Hu Wang Chen-Chen zhou Sha Liu Jin Yao Qin Jiang Nanjing Medical University Affiliated Eye Hospital Nanjing 290091Jiangsu ProvinceChina

AIM:To compare the short-term effectiveness of intelligent navigated laser photocoagulation and 577-nm subthreshold micropulse laser(SML)treatment in patients with chronic central serous chorioretinopathy(cCSC).METHODS:This observational retrospective cohort study included 60 consecutive patients who underwent intelligent navigated laser photocoagulation(n=30)or 577-nm SML treatment(n=30)for cCSC between Jan.2021 and *** 3mo follow-up,all patients underwent assessments of best correct visual acuity(BCVA)and optical coherence tomography(OCT).RESULTS:The operation of laser treatment was successful in all *** 1mo,BCVA improved significantly more in the intelligent navigated laser photocoagulation group compared to the SML group(P0.05).Central macular thickness(CMT)in the intelligent navigated laser photocoagulation group was lower than in the SML group at 1mo(P0.05).CONCLUSION:Intelligent navigated laser photocoagulation is superior to SML for treating cCSC,leading to better improvements in vision and CMT for short term.

关键词： intelligent navigated laser photocoagulation subthreshold micropulse laser central serous chorioretinopathy optical coherence tomography

Decreased Nrf2 protein level and low sperm quality in intractable spermatocystitis

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Asian Journal of Andrology 2024年第2期26卷 189-194页

作者： Shi-Ze Wang Jian-Nan Liu fen-Fang zhou Ye-Jin-Peng Wang Peng Zhang Song-Tao Cheng Department of Urology Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072China Department of Urology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Health Management and Clinical Medicine School of Medicine and HealthWuhan PolytechnicUniversityWuhan 430071China

To investigate the molecular etiology of low sperm quality in patients with intractable spermatocystitis,spermatozoa samples from patients with persistent hematospermia undergoing transurethral seminal vesiculoscopy and healthy volunteers were *** samples were collected from the seminal vesicles through transurethral seminal vesiculoscopy or by masturbation *** quality was analyzed by a WLJY-9000 color semen analysis *** of tumor necrosis factor alpha(TNFa)and interleukin-6(IL-6)in the seminal plasma was performed using enzyme-linked immunosorbent assay(ELISA).Measurement of H_(2)O_(2)in the seminal plasma was performed with a hydrogen peroxide *** protein levels of nuclear factor erythroid 2-related factor 2(Nrf2)and phosphorylated-Nrf2(p-Nrf2)were measured by western blot analysis and immunofluorescence *** sperm quality parameters and increased levels of inflammatory cytokines(TNFa,IL-6,and H_(2)O_(2))in the seminal plasma were detected among the semen samples from the patients with persistent ***2 and p-Nrf2 were strongly expressed in the nucleus and periphery of human sperm cells,according to the results of the immunofluorescence *** protein levels of Nrf2 and p-Nrf2 were significantly lower in the spermatozoa samples from patients with persistent hematospermia than in those from healthy volunteers with normal sperm *** results suggested that Nrf2 signaling might play a role in the low sperm quality of patients with intractable spermatocystitis.

关键词： H_(2)O_(2) Nrf2 sperm quality spermatocystitis