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Preparation of W-TiC alloys from core-shell structure powders synthesized by an improved wet chemical method

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Rare Metals 2023年第4期42卷 1378-1386页

作者： shao-ting Lang Qing-Zhi Yan Ning-Bo Sun Xiao-Xin Zhang Institute of Nuclear Materials University of Science and Technology BeijingBeijing100083China

In order to improve the homogeneous distribution of the TiC particles and facilitate the TiC particles to distribute in the tungsten grain interiors,two kinds of TiCdoped tungsten precursors with a core-shell structure were prepared by an improved wet chemical method at different reaction temperature ***,fine platelike precursor(200-400 nm)and flower-like precursor(approximately 1.25μm)are *** reduction and sintering,the microstructures of the samples were characterized by scanning electron microscopy and transmission electron *** the sample sintered from the platelike precursor,TiC particles with sizes in the range of40-300 nm and an average size of approximately 80 nm were uniformly distributed in the tungsten matrix with a high share in the grain ***,in the sample sintered from the flower-like precursor,the TiC particles with sizes in the range of 50-700 nm are significantly aggregated and non-uniformly distributed in the tungsten *** a result,the sample sintered from the plate-like precursor achieves higher mechanical properties and a much narrower range of bending strength values than that sintered from the flower-like *** average bending strength of the sample sintered from the plate-like precursor is 655 MPa,which is higher than that of the sample sintered from the flower-like precursor(524 MPa).Different reaction mechanisms and dispersing stabilities of the TiC particles at different temperature conditions should be accounted for the differences between the two samples.

关键词： Wet chemical method W-TiC alloy Core-shell structures Spark plasma sintering Microstructure characterization

Diurnal expression of circadian clock genes period 1 and period 3 in Pelteobagrus vachellii

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Journal of Oceanology and Limnology 2021年第2期39卷 652-660页

作者： Chuanjie QIN ting shao Xufeng LIAO Yang HE Jun WANG Peng HU Key Laboratory of Sichuan Province for Fishes Conservation and Utilization in the Upper Reaches of the Yangtze River Neijiang Normal UniversityNeijiang 641112China College of Life Science Neijiang Normal UniversityNeijiang 641112China

Circadian clock genes are crucial for generating and sustaining most rhythmic daily functions in the animal kingdom,which entrain the rhythms of biochemical,physiological,and behavioural *** better understand the molecular oscillations of the circadian rhythms in darkbarbel catfish(Pelteobagrus vachellii),we isolated and characterized two circadian clock genes in ***,period 1(per1),and period 3(per3).The circadian clock gene per1 was found to encode a 1428-amino acid polypeptide,including PER-ARNT-SIM(PAS)dimerisation domains,a PAS-associated C-terminal motif(PAC),a short mutable domain(S/M),and a nuclear export signal(NES).The 4902-bp per3 cDNA includes an open reading frame encoding a 1292-amino acid residue polypeptide with a PER-ARNT-SIM(PAS)domain,cytoplasmic localisation domain(CLD),interaction site(TIS),and a nuclear localisation signal(NLS).The per1 and per3 gene was constitutively expressed in all examined ***,per1 expression within a light/dark cycles showed rhythmic expression in the diencephalon,brain,liver and intestine,with the acrophase at 15:15,12:52,7:51 and 12:55,*** expression of per3 was rhythmic in the diencephalonbrain,liver and intestine,with the acrophase at 8:15,9:54,10:39,and 10:25 h,*** findings expand our understanding of circadian mechanism at the molecular level in this species.

关键词： cDNA circadian rhythm diurnal expression Pelteobagrus vachellii period 1 period 3

Reassessing the Lewis Turning Point in China： Evidence from 70,000 Rural Households

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China & World Economy 2018年第1期26卷 4-17页

作者： Yuan Zhang ting shao Qi Dong China Center for Economic Studies Fudan University China Development Research Center of the State Council China. Hanqing Advanced Institute of Economics and and Finance Renmin University China

There is no convincing evidence to prove that China＇s Lewis turning point （LTP） arrived in 2004-2005, as suggested in some of the existing literature. Employing data from the National Bureau of Statistics of China for 70,000 rural households and following the method proposed by Minami （1968） to identify the Lewis turning point in Japan, the present study reassessed the reaching of the LTP in China and found that China＇s economy reached the LTP around 2010. From a regional perspective, China ＂s eastern region reached the LTP in 2010 and its central and western regions are now approaching the turning point. After arriving at the LTP, China＇s rural economy will face three key tasks.＂ safeguarding grain security, promoting economic restructuring and realizing agricultural modernization. To cope with the shortage of human capital in agriculture production and the challenge of the tight balance between grain supply and demand, the Chinese Government should improve the human capital training system, accelerate agricultural modernization and guarantee national grain security.

关键词： grain security Lewis turning point marginal labor productivity rural household data

Lead-free bilayer heterometallic halide perovskite with reversible phase transition and photoluminescence properties

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Chinese Chemical Letters 2023年第4期34卷 590-594页

作者： Qiangqiang Jia ting shao Liang Tong Changyuan Su Dawei Fu Haifeng Lu Institute for Science and Applications of Molecular Ferroelectrics Key Laboratory of the Ministry of Education for Advanced Catalysis MaterialsZhejiang Normal UniversityJinhua 321004China Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and Applications of Molecular FerroelectricsSoutheast UniversityNanjing 211189China School of Environment and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212002China

The layered heterometallic halide perovskites, as a newly explored material, have attracted great scientific attention. As one of the representatives of perovskite, lead-free or lead-substituted perovskite materials are widely applied in photovoltaic, sensors, catalysis, detectors and other fields. Therefore, it is urgent to carry out more systematic exploration and expand applicable preresearch, so as to make more interesting discoveries in this new hot spot. As an interesting candidate, heterometallic compounds will introduce more structural adjustability and novel physical properties, which is the main feature to be selected as the research hotspot. Here, we reported a lead-free bilayer heterometallic Ruddlesden-Popper(RP) type perovskite, [(MACH)_(2)CsAgBiBr_(7)](MACH = cyclohexanemethylamine), which possesses a reversible phase transition at 379.6 K/375.1 K during heating-cooling cycle. Besides, it exhibits reddish-brown light emission under 365 nm, meanwhile, CIE chromaticity coordinate is(0.32, 0.45) on the yellow side and correlated color temperature is about 6000 K. Moreover, both the experimental data and theoretical calculation results suggest that [(MACH)_(2)CsAgBiBr_(7)] shows indirect semiconducting characteristics. In summary, this work will inspire the design of lead-free heterometallic perovskite materials for the application of sensors and light-emitting diodes(LEDs) fields.

关键词： Lead-free Heterometallic Perovskite Phase transition Photoluminescence

Lung function and air pollution exposure in adults with asthma in Beijing:a 2-year longitudinal panel study

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Frontiers of Medicine 2022年第4期16卷 574-583页

作者： Jun Wang Wenshuai Xu Xinlun Tian Yanli Yang shao-ting Wang Kai-Feng Xu Department of Pulmonary and Critical Care Medicine Peking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100730China

The effect of air pollution on the lung function of adults with asthma remains unclear to *** study followed 112 patients with asthma at 3-month intervals for 2 *** pollutant exposure of the participants was estimated using the inverse distance weight *** participants were divided into three groups according to their lung function level at every visit.A linear mixed-effect model was applied to predict the change in lung function with each unit change in pollution *** to carbon monoxide(CO)and particles less than 2.5 micrometers in diameter(PM2.5)was negatively associated with large airway function in *** the severe group,exposure to chronic sulfur dioxide(SO2)was negatively associated with postbronchodilator forced expiratory flow at 50%,between 25%and 75%of vital capacity%predicted(change of 95%CI per unit:-0.34(-0.55,-0.12),-0.24(-0.44,-0.03),respectively).In the mild group,the effect of SO2 on the small airways was similar to that in the severe group,and it was negatively associated with large airway *** to CO and PM2.5 was negatively associated with the large airway function of adults with *** negative effects of SO2 were more evident and widely observed in adults with severe and mild asthma than in adults with moderate *** with asthma react differently to air pollutants as evidenced by their lung function levels.

关键词： lung function asthma air pollution adult

Comparison of efficacy of two different silicone hydrogel bandage contact lenses after T-PRK

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International Journal of Ophthalmology(English edition) 2022年第2期15卷 299-305页

作者： Hua Li ting shao Jia-Fan Zhang Lin Leng Sai Liu Ke-Li Long Qingdao Eye Hospital of Shandong First Medical University State Key Laboratory Cultivation BaseShandong Provincial Key Laboratory of OphthalmologyEye Institute of Shandong First Medical UniversityQingdao 266071Shandong ProvinceChina

AIM:To compare the efficacy between two different silicone hydrogel bandage contact lenses after transepithelial photorefractive keratectomy(T-PRK).METHODS:In this randomized controlled trial,a total of 89 patients(178 eyes) who underwent T-PRK at the Qingdao Eye Hospital from October to December 2019 were *** random eye wore a Senofilcon A bandage contact lens after surgery,and the other eye a Balafilcon A bandage contact *** scores,uncorrected visual acuity(UCVA),spherical equivalent(SE),corneal epithelial healing status,epithelial thickness,bandage lenses deposits,lenses movement,and ocular surface conditions were measured and ***:There were no differences between the two groups in UCVA,SE,corneal epithelial healing status,corneal epithelial thickness,tear river heights and tear film rupture time at each follow-up ***,postoperative pain scores in the Senofilcon A group were significantly lower than those of the Balafilcon A group(F_(intergroups)=67.833,P<0.001;F_(time)=383.773,P<0.001;F_(interaction)=57.344,P<0.001).The duration of pain in eyes in the Senofilcon A group was shorter than that of the Balafilcon A group(t=-3.326,P=0.001).The surface deposition scores and movement scores of Senofilcon A bandage lenses on the first and fourth days after surgery were lower than those of Balafilcon A bandage lenses(Z=-5.385,-6.782,P<0.001;Z=-8.336,-8.906,P<0.001).CONCLUSION:Both Senofilcon A and Balafilcon A bandage lenses have good efficacy after *** A lenses are associated with less pain and more comfort compared to Balafilcon A.

关键词： transepithelial photorefractive keratectomy bandage contact lenses corneal epithelium pain clinical results

19F NMR Study of the Bilayer Iron-Based Superconductor KCa2Fe4As4F2

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Chinese Physics Letters 2019年第12期36卷 67-69页

作者： Yu-ting shao Wen-Shan Hong Shi-Liang Li Zheng Li Jian-Lin Luo Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190 School of Physical Sciences University of Chinese Academy of SciencesBejjing 100190 Songshan Lake Materials Laboratory Dongguan 523808

We report a^19F nuclear magnetic resonance(NMR)study on single-crystal KCa2 Fe4As4F2(Tc^33.3 K).The 19F NMR spectral shape of KCa2Fe4As4F2 is weakly dependent on temperature and the Knight shift is small,which implies weak coupling between the Ca F layer and the Fe As *** temperature dependence of 1/^19T1 shows a hump below Tc,however the 1/^75T1 decreases just below Tc,which implies that there are strong in-plane magnetic fluctuations in the Ca F layers than in the Fe As *** may be caused by the motion of *** absence of the coherence peak suggests unconventional superconductivity in KCa2Fe4As4F2.

关键词： layer NMR implies

Total laparoscopic hysterectomy after liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2010年第4期9卷 438-440页

作者： Zhu, Hai-Bing Jin, Yue Xu, shao-ting Xia, Ya-Xian Xie, Li-Ping Zhejiang Univ Sch Med Affiliated Hosp 1 Dept Urol Hangzhou 310003 Zhejiang Peoples R China Zhejiang Univ Sch Med Affiliated Hosp 1 Dept Obstet & Gynecol Hangzhou 310003 Zhejiang Peoples R China

BACKGROUND: The number of females who undergo liver transplantation is growing and sometimes gynecologic operations are needed to control gynecologic diseases after liver transplantation. METHOD: Total laparoscopic hysterectomy was performed in 2 patients who had undergone liver transplantation, one for adenomyosis and the other for hysteromyoma. RESULTS: It was safe to create a pneumoperitoneum through the umbilical skinfold even though mild adhesion in the pelvic cavity occurred in one patient. The operative times were 95 and 90 minutes, with blood loss of about 100 and 60 ml, respectively. Oral intake, flatus passage, and ambulation recovered within a day, after the operation. No significant changes in liver function were observed except complication of diarrhea caused by Candida albicans in one patient. CONCLUSIONS: The result of the two patients suggest that total laparoscopic hysterectomy is a safe and effective surgical approach for patients who have undergone liver transplantation.

关键词： total laparoscopic hysterectomy liver transplantation immunosuppression

Accumulation of Nitrate in Vegetables and Its Possible Implications to Human Health

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Agricultural Sciences in China 2007年第10期6卷 1246-1255页

作者： DU shao-ting ZHANG Yong-song LIN Xian-yong Key Lab of Environmental Remediation and Ecosystem Health Ministry of Education/College of Environmental and Resources SciencesZhejiang University Hangzhou 310029 P.R.China

In recent times, there are two kinds of completely opposite viewpoints about the impacts of nitrate on human health. To further objectively understand the effects of nitrate on human health, both of harmfulness and possible benefits of nitrate to human body., it is discussed in this review from the aspects of nitrate accumulation in vegetables, the source of nitrate ingested into human body, and the transformation of nitrate in human body, as well as the pathogenesis and physiological functions of nitrate metabolism.

关键词： vegetable nitrate methemoglobin carcinogenesis human health NO bacteria