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| 1 | Characteristics of Settings and Etiologic Agents of Foodborne Disease Outbreaks—China,2020显示文摘Introduction:Foodborne diseases are a growing public health problem and have caused a large burden of disease in China.This study analyzed epidemiological characteristics of foodborne diseases in China in 2020 to provide a scientific basis for prevention and control measures.Methods:Data were collected from 30 of 31 provincial-level administrative divisions(PLADs)in the mainland of China,excluding Xizang(Tibet)Autonomous Region,via the National Foodborne Disease Outbreaks Surveillance System・The number and proportion of outbreaks,illnesses,hospitalizations,deaths by setting,pathogen-food category pairs and etiology were calculated.Results:In 2020,7,073 foodborne disease outbreaks were reported,resulting in 37,454 illnesses and 143 deaths.Among the identified pathogens,microbial pathogens were the most common confirmed etiology,accounting for 41.7%of illnesses.Poisonous mushrooms caused the largest proportion of outbreaks(58.0%)and deaths(57.6%).For venues where foodborne disease outbreaks occur,household had the highest number of outbreaks(4,140)and deaths(128),and catering service locations caused the largest proportion of illnesses(59.9%).Outbreaks occurring between June and September accounted for 62.8%of total outbreaks.Conclusions:Foodborne disease outbreaks mainly occurred in households・Microbial pathogens remained the top cause of outbreak-associated illnesses.Poisonous mushrooms were ranked the top cause of deaths in private homes in China.The supervision and management of food safety and health education should be strengthened to reduce the burden of foodborne diseases・Publicity should be increased to reduce the incidence of mushroom poisonings in families,and supervision and management of food should be strengthened to reduce microbial contamination. | Hongqiu Li Weiwei Li Yue Dai Yuyan Jiang Junhua Liang Santao Wang Maoqiang Zhuang Zheng Huang Lizi Xu Bo Xue Jikai Liu Haihong Han Sara M.Pires Ping Fu Yunchang Guo | 2021 | China CDC weekly2021，3，42： | 14 |
| 2 | Mortality outcomes of low-dose computed tomography screening for lung cancer in urban China:a decision analysis and implications for practice显示文摘Background: Mortality outcomes in trials of low-dose computed tomography(CT) screening for lung cancer are inconsistent. This study aimed to evaluate whether CT screening in urban areas of China could reduce lung cancer mortality and to investigate the factors that associate with the screening effect.Methods: A decision tree model with three scenarios(low-dose CT screening, chest X-ray screening, and no screening) was developed to compare screening results in a simulated Chinese urban cohort(100,000 smokers aged45-80 years). Data of participant characteristics were obtained from national registries and epidemiological surveys for estimating lung cancer prevalence. The selection of other tree variables such as sensitivities and specificities of low-dose CT and chest X-ray screening were based on literature research. Differences in lung cancer mortality(primary outcome), false diagnoses, and deaths due to false diagnosis were calculated. Sensitivity analyses were performed to identify the factors that associate with the screening results and to ascertain worst and optimal screening effects considering possible ranges of the variables.Results: Among the 100,000 subjects, there were 448,541, and 591 lung cancer deaths in the low-dose CT, chest X-ray, and no screening scenarios, respectively(17.2% reduction in low-dose CT screening over chest X-ray screening and 24.2% over no screening). The costs of the two screening scenarios were 9387 and 2497 false diagnoses and 7and 2 deaths due to false diagnosis among the 100,000 persons, respectively. The factors that most influenced death reduction with low-dose CT screening over no screening were lung cancer prevalence in the screened cohort, lowdose CT sensitivity, and proportion of early-stage cancers among low-dose CT detected lung cancers. Considering all possibilities, reduction in deaths(relative numbers) with low-dose CT screening in the worst and optimal cases were16(5.4%) and 288(40.2%) over no screening, respectively.Conclusions: In terms of mortality outcomes, our findings favor conducting low-dose CT screening in urban China.However, approaches to reducing false diagnoses and optimizing important screening conditions such as enrollment criteria for screening are highly needed. | Zixing Wang Wei Han Weiwei Zhang Fang Xue Yuyan Wang Yaoda Hu Lei Wang Chunwu Zhou Yao Huang Shijun Zhao Wei Song Xin Sui Ruihong Shi Jingmei Jiang | 2017 | Chinese Journal of Cancer2017，36，8： | 9 |
| 3 | Receptome profiling identifies KREMEN1 and ASGR1 as alternative functional receptors of SARS-CoV-2显示文摘Host cellular receptors play key roles in the determination of virus tropism and pathogenesis.However,little is known about SARS-CoV-2 host receptors with the exception of ACE2.Furthermore,ACE2 alone cannot explain the multi-organ tropism of SARS-CoV-2 nor the clinical differences between SARS-CoV-2 and SARS-CoV,suggesting the involvement of other receptor(s).Here,we performed genomic receptor profiling to screen 5054 human membrane proteins individually for interaction with the SARS-CoV-2 capsid spike(S)protein.Twelve proteins,including ACE2,ASGR1,and KREMEN1,were identified with diverse S-binding affinities and patterns.ASGR1 or KREMEN1 is sufficient for the entry of SARS-CoV-2 but not SARS-CoV in vitro and in vivo.SARS-CoV-2 utilizes distinct ACE2/ASGR1/KREMEN1(ASK)receptor combinations to enter different cell types,and the expression of ASK together displays a markedly stronger correlation with virus susceptibility than that of any individual receptor at both the cell and tissue levels.The cocktail of ASK-related neutralizing antibodies provides the most substantial blockage of SARS-CoV-2 infection in human lung organoids when compared to individual antibodies.Our study revealed an interacting host receptome of SARS-CoV-2,and identified ASGR1 and KREMEN1 as alternative functional receptors that play essential roles in ACE2-independent virus entry,providing insight into SARS-CoV-2 tropism and pathogenesis,as well as a community resource and potential therapeutic strategies for further COVID-19 investigations. | Yunqing Gu Jun Cao Xinyu Zhang Hai Gao Yuyan Wang Jia Wang Juan He Xiaoyi Jiang Jinlan Zhang Guanghui Shen Jie Yang Xichen Zheng Gaowei Hu Yuanfei Zhu Shujuan Du Yunkai Zhu Rong Zhang Jianqing Xu Fei Lan Di Qu Guoliang Xu Yun Zhao Dong Gao Youhua Xie Min Luo Zhigang Lu | 2022 | Cell Research2022，32，1： | 8 |
| 4 | Differences of Hydrocarbon Enrichment between the Upper and the Lower Structural Layers in the Tazhong Paleouplift显示文摘Tazhong paleouplift 被划分成上面并且更低的结构的层,在奥陶纪碳酸盐岩石的顶由不顺从表面跳了。在从不同部分的二层的水库在数字变化,类型和储备,而是机制以前很少被研究。因此,机制的解释将在 Tazhong paleouplift 支持石油探索。在学习进化和 Tazhong paleouplift 的水库分发以后,在晚古苏格兰的、迟了的 Hercynian 和喜玛拉雅的时期的进化导致了,这被结束上面并且更低的结构的层。这也被定义在上面的结构的层,结构并且, stratigraphic 重叠水库为更低的结构的层在顶和 paleouplift 的上面的部分被开发,它被油水库统治, lithological 水库在 paleouplift 的更低的部分被开发,它被煤气的水库,和更多统治储备在更低的结构的层被发现比上面。通过累积条件的比较分析上面并且更低的结构的层,丰富差别的机制清楚地被解释。更低的结构的层的水库和封口条件比上面的层的那些好,它是更多的水库在前者被发现了的原因。在搬运人系统类型,陷井类型和收费时期在之间的差别上面并且更低的结构的层在水库类型和分布导致差别。一个累积模型为 Tazhong paleouplift 被建立。为上面的结构的层,,结构的水库和 stratigraphic 重叠水库为更低的结构的层在 paleouplift 的上面的部分被形成,捱过的外壳水库在顶被形成,礁石公寓水库在侧面的边缘上被形成,石灰岩地区常见的地形和里面水库在 paleouplift 的更低的部分被形成。 | JIANG Zhenxue YANG Haijun LI Zhuo PANG Xiongqi HAN Jianfa LI Dongxu HUANG Yuyan | 2010 | Acta Geologica Sinica(English Edition)2010，84，5： | 7 |
| 5 | 中国城市人群低剂量计算机断层扫描筛查肺癌的死亡率结果:决策分析和实践意义显示文摘背景与目的不同低剂量计算机断层扫描(computed tomography,CT)筛查肺癌试验得出的死亡率结果不一致。本研究旨在评价中国城市CT筛查是否能够降低肺癌死亡率,并探讨影响筛查效果的因素。方法建立了3种场景(低剂量CT筛查、胸部X线筛查和无筛查)的决策树模型来比较模拟的中国城市人群(100,000例年龄45–80岁的吸烟者)的筛查结果。从国家登记和流行病学调查中获得了参与者特征数据并估算了肺癌患病比例。根据文献调研选择了低剂量CT和胸部X线筛查的灵敏度和特异度等其他树变量。计算了3种筛查方法间肺癌死亡率(主要结局)、误诊和误诊导致死亡的差异。通过敏感性分析找出了与筛查结果相关的因素,并确定了在变量可能范围内的最差和最优筛查效果。结果 100,000例研究对象中,低剂量CT、胸部X线和无筛查场景分别有448例、541例和591例肺癌死亡(低剂量CT筛查比胸部X线筛查死亡人数减少17.2%,比无筛查减少24.2%)。100,000例研究对象中,2种筛查场景的代价分别为9387例和2497例误诊及7例和2例误诊导致的死亡。低剂量CT筛查比无筛查的死亡数降低,影响最大的因素是筛查人群的肺癌患病比例、低剂量CT的灵敏度和低剂量CT检出肺癌中早期癌的比例。综合了所有可能性,低剂量CT筛查肺癌的死亡人数(相对数)在最坏和最好情况下分别比无筛查降低了16例(5.4%)和288例(40.2%)。结论就死亡率结局而言,我们的研究结果支持在中国城市人群中进行低剂量CT筛查。然而,急需策略来减少误诊和优化纳入标准等重要筛查条件。 | Zixing Wang Wei Han Weiwei Zhang Fang Xue Yuyan Wang Yaoda Hu Lei Wang Chunwu Zhou Yao Huang Shijun Zhao Wei Song Xin Sui Ruihong Shi Jingmei Jiang | 2018 | 癌症2018，37，8： | 3 |
| 6 | pH-sensitive and biodegradable charge-transfer nanocomplex for second near-infrared photoacoustic tumor imaging显示文摘The emerging technique of photoacoustic imaging,especially in the near infra-red(NIR)window,permits high resolution,deep-penetration,clinically reliable sensing.However,few contrast agents are available that can specifically respond to intricate biological environments,and which are biodegradable and biocompatible.Herein,we in troduce a new class of pH-sensitive orga nic photoacoustic con trast age nt that operates in the second NIR window(NIR-II,960-1,700 nm),which is derived from the self-assembled charge-transfer nanocomplex(CTN)by 3,3',5,5'-tetramethylbenzidine(TMB)and its dication structure(TMB++).The unique NIR-ll-responsive CTN can specifically respond to pH change in the physiological range and allows noninvasive and sensitive visualization of the tumor acidic microenvironment(e.g.at pH5)in mice with higher signal-to-noise ratio.The CTN is biodegradable under physiological conditions(e.g.pH 7.4),which alleviates the biosafety concern of nan oparticle accumulati on in vivo.These results clearly show the pote ntial of the TMB/TMB++-based CTN as a promisi ng pH-activated and biodegradable molecular probe for specific tumor photoacoustic imaging in the NIR-II region. | Zhimin Wang Paul Kumar Upputuri Xu Zhen Ruochong Zhang Yuyan Jiang Xiangzhao Ai Zhijun Zhang Ming Hu Zhenyu Meng Yunpeng Lu Yuanjing Zheng Kanyi Pu Manojit Pramanik Bengang Xing | 2019 | Nano Research2019，12，1： | 3 |
| 7 | Challenges and research opportunities for lung cancer screening in China显示文摘Following publication of the results of the National Lung Screening Trial in the United States,a randomized controlled trial in Italy(ITALUNG)and two simulation studies in China reported similar findings in 2017 favoring lung cancer screening with low-dose computed tomography among smokers.With such advances in lung cancer screening,worldwide interest has gradually shifted from evaluating whether refining lung cancer screening protocols is effective in preventing deaths.However,there are several practical problems to be resolved,including the balance of enroll-ment criteria and cost effectiveness,precise measurements to reduce false positive findings,risk-based optimization of screening frequency,challenges associated with cancer heterogeneity,strategies to combine image screening with novel biomarkers,dynamic monitoring of the natural history of cancer,accurate identification and diagnosis of cases among huge populations,and the impact of tobacco control policy and environment protection.As one in three individuals with lung cancer worldwide resides in China,these questions pose great challenges as well as research opportunities for population screening programs in China. | Zixing Wang Yuyan Wang Yao Huang Fang Xue Wei Han Yaoda Hu Lei Wang Wei Song Jingmei Jiang | 2018 | Cancer Communications2018，38，1： | 3 |
| 8 | Chemotherapy initiation with single-course methotrexate alone or combined with dactinomycin versus multi-course methotrexate for low-risk gestational trophoblastic neoplasia: a multi-centric randomized clinical trial显示文摘We aimed to evaluate the effectiveness and safety of single-course initial regimens in patients with low-risk gestational trophoblastic neoplasia(GTN).In this trial (NCT01823315),276 patients were analyzed.Patients were allocated to three initiated regimens:single-course methotrexate(MTX),single-course MTX+dactinomycin(ACTD),and multi-course MTX(control arm).The primary endpoint was the complete remission(CR)rate by initial drug(s).The primary CR rate was 64.4%with multi-course MTX in the control arm.For the single-course MTX arm,the CR rate was 35.8%by one course;it increased to 59.3%after subsequent multi-course MTX,with non-inferiority to the control(difference-5.1%,95%confidence interval(CI)-19.4%to 9.2%,P=0.014).After further treatment with multi-course ACTD,the CR rate(93.3%)was similar to that of the control(95.2%,P=0.577).For the single-course MTX+ACTD arm,the CR rate was 46.7%by one course,which increased to 89.1%after subsequent multi-course,with non-inferiority(difference 24.7%,95%CI 12.8%-36.6%,P<0.001)to the control.It was similar to the CR rate by MTX and further ACTD in the control arm(89.1%vs.95.2%,P=0.135).Four patients experienced recurrence,with no death,during the 2-year follow-up.We demonstrated that chemotherapy initiation with single-course MTX may be an alternative regimen for patients with low-risk GTN. | Lili Chen Ling Xi Jie Jiang Rutie Yin Pengpeng Qu Xiuqin Li Xiaoyun Wan Yaxia Chen Dongxiao Hu Yuyan Mao Zimin Pan Xiaodong Cheng Xinyu Wang Qingli Li Danhui Weng Xi Zhang Hong Zhang Quanhong Ping Xiaomei Liu Xing Xie Beihua Kong Ding Ma Weiguo Lu | 2022 | Frontiers of Medicine2022，16，2： | 2 |
| 9 | An Efficient Summer Operation Scheme for a Thermal Power Plant Air Cooling System based on Electric Peak Shaving显示文摘We proposed a novel efficient operation scheme for a thermal power plant’s air-cooling system based on peak shaving, in order to cope with high ambient temperature in summer. We introduced an absorptiongeneration equipment with water/lithium working pairs into the air cooled condenser(ACC) to reconstruct the traditional thermal power plant, and established a dynamic thermodynamic model adopting Ebsilon code. We studied the thermodynamic performance variation of the reconstructed thermal power plant throughout a 24-hour cycle and found that the fluctuation ratio of the turbine back pressure decreased to 6% from 78%, which is beneficial for the stable and safe operation of the electric power system. The thermal performance improvement benefited from the exploitation of the heat transfer potential of ACC, which realized via cold duty schedule throughout the day, under different ambient temperature conditions. In this system, the generated power was higher at relatively high ambient temperature than that at relatively low ambient temperature, which solved the electricity demand-supply imbalance problem under high ambient temperature. Finally, the same optimization effects for power thermal plants with an indirect air-cooling system were obtained using the same operation scheme. | HU Hemin LIANG Shiqiang JIANG Yuyan GUO Yongxian | 2020 | Journal of Thermal Science2020，29，2： | 2 |
| 10 | WRF-Chem simulation of East Asian air quality: Sensitivity to temporal and vertical emissions distributions显示文摘 | Xueyuan Wang Xin-Zhong Liang Weimei Jiang Zhining Tao Julian X.L. Wang Hongnian Liu Zhiwei Han Shuyan Liu Yuyan Zhang Georg A. Grell Steven E. Peckham | 2009 | Atmospheric Environment2009，，5： | 1 |
| 11 | Low-depth whole genome sequencing reveals copy number variations associated with higher pathologic grading and more aggressive subtypes of lung non-mucinous adenocarcinoma显示文摘Objective:Histology grade,subtypes and TNM stage of lung adenocarcinomas are useful predictors of prognosis and survival.The aim of the study was to investigate the relationship between chromosomal instability,morphological subtypes and the grading system used in lung non-mucinous adenocarcinoma(LNMA).Methods:We developed a whole genome copy number variation(WGCNV)scoring system and applied next generation sequencing to evaluate CNVs present in 91 LNMA tumor samples.Results:Higher histological grades,aggressive subtypes and more advanced TNM staging were associated with an increased WGCNV score,particularly in CNV regions enriched for tumor suppressor genes and oncogenes.In addition,we demonstrate that 24-chromosome CNV profiling can be performed reliably from specific cell types(<100 cells)isolated by sample laser capture microdissection.Conclusions:Our findings suggest that the WGCNV scoring system we developed may have potential value as an adjunct test for predicting the prognosis of patients diagnosed with LNMA. | Zheng Wang Lin Zhang Lei He Di Cui Chenglong Liu Liangyu Yin Min Zhang Lei Jiang Yuyan Gong Wang Wu Bi Liu Xiaoyu Li David S Cram Dongge Liu | 2020 | Chinese Journal of Cancer Research2020，32，3： | 1 |
| 12 | Ethacrynic acid targets GSTM1 to ameliorate obesity by promoting browning of white adipocytes显示文摘Dear Editor,Obesity is caused by an imbalance between energy intake and expenditure,and has become a global epidemic with over 650 million adults affected.Adipose tissues in mammals are composed of white adipose tissue(WAT)and classical brown adipose tissue(BAT),and their balance is highly related to the occurrence of obesity.The browning of white adipocytes results in“beige”or“brite”adipocytes,which appear functionally similar to classical brown adipocytes,and can be detected in WAT deposits of animals that have been exposed to cold or other inducers(Fu et al.,2015). | Zhaomeng Cui Yang Liu Wei Wan Yuyan Xu Yehui Hu Meng Ding Xin Dou Ruina Wang Hailing Li Yongmei Meng Wei Li Wei Jiang Zengxia Li Yiming Li Minjia Tan Dengke KMa Yu Ding Jun OLiu Cheng Luo Biao Yu Qiqun Tang Yongjun Dang | 2021 | Protein & Cell2021，12，6： | 1 |
| 13 | Dynamic Modeling on Bubble Growth, Detachment and Heat Transfer for Hybrid-Scheme Computations of Nucleate Boiling 显示文摘 | Jiang Yuyan Osada Hiroshi Irmgaki Masahide | 2013 | lnt J Heat Mass Transfer2013，56，12： | 1 |
| 14 | Microglia in neurodegenerative diseases: mechanism and potential therapeutic targets显示文摘Microglia activation is observed in various neurodegenerative diseases.Recent advances in single-cell technologies have revealed that these reactive microglia were with high spatial and temporal heterogeneity.Some identified microglia in specific states correlate with pathological hallmarks and are associated with specific functions. | Chao Gao Jingwen Jiang Yuyan Tan Shengdi Chen | 2023 | Signal Transduction and Targeted Therapy2023，8，10： | 1 |
| 15 | A non-ACE2 competing human single-domain antibody confers broad neutralization against SARS-CoV-2 and circulating variants显示文摘The current COVID-19 pandemic has heavily burdened the global public health system and may keep simmering for years.The frequent emergence of immune escape variants have spurred the search for prophylactic vaccines and therapeutic antibodies that confer broad protection against SARS-CoV-2 variants.Here we show that the bivalency of an affinity maturated fully human singledomain antibody(n3113.1-Fc)exhibits exquisite neutralizing potency against SARS-CoV-2 pseudovirus,and confers effective prophylactic and therapeutic protection against authentic SARS-CoV-2 in the host cell receptor angiotensin-converting enzyme 2(ACE2)humanized mice.The crystal structure of n3113 in complex with the receptor-binding domain(RBD)of SARS-CoV-2,combined with the cryo-EM structures of n3113 and spike ecto-domain,reveals that n3113 binds to the side surface of up-state RBD with no competition with ACE2.The binding of n3113 to this novel epitope stabilizes spike in up-state conformations but inhibits SARS-CoV-2 S mediated membrane fusion,expanding our recognition of neutralization by antibodies against SARS-CoV-2.Binding assay and pseudovirus neutralization assay show no evasion of recently prevalent SARS-CoV-2 lineages,including Alpha(B.1.1.7),Beta(B.1.351),Gamma(P.1),and Delta(B.1.617.2)for n3113.1-Fc with Y58L mutation,demonstrating the potential of n3113.1-Fc(Y58L)as a promising candidate for clinical development to treat COVID-19. | Zhenlin Yang Yulu Wang Yujia Jin Yuanfei Zhu Yanling Wu Cheng Li Yu Kong Wenping Song Xiaolong Tian Wuqiang Zhan Ailing Huang Shanshan Zhou Shuai Xia Xiaoxu Tian Chao Peng Cuicui Chen Yibing Shi Gaowei Hu Shujuan Du Yuyan Wang Youhua Xie Shibo Jiang Lu Lu Lei Sun Yuanlin Song Tianlei Ying | 2021 | Signal Transduction and Targeted Therapy2021，6，12： | 1 |
| 16 | Variation in egg size and nestling growth rate in relation to clutch size and laying sequence in great tits Parus major显示文摘The objectives of this study were to examine (1) optimal clutch size in great tits (Parus major) nesting in nest boxes; (2) variation in egg morphology and nestling growth rate with position in the laying sequence; and (3) hatching asynchrony and nestling survival as determined by infrared nest cameras. We collected data from 73 clutches in artificial nest boxes in the Zuojia Natural Preserve area in Jilin Province, China, in 2005 and 2006, using infrared cameras to match laying order to hatching order for four nests. Egg morphology and growth rate were significantly affected by clutch size and position in the laying order. Overall, egg size and growth rate increased with position in the laying order. In general, it was diffcult to detect asynchronous hatching from observations alone, but data from our infrared cameras showed that early-laid eggs tended to hatch before later-laid eggs, leading to hatching asynchrony. However, females invested more into last-laid eggs and nestlings, reducing size asynchrony among the chicks and leading to higher survival rates of nestlings. Our results, therefore, provide support for the 'brood survival' hypothesis rather than for the'brood reduction' hypothesis. | Yuyan You Jiang Feng Haitao Wang Jilong Wang Chao Dong Xunrui Su Hanmei Sun Wei Gao | 2009 | Progress in Natural Science:Materials International2009，19，4： | 0 |
| 17 | Construction and analysis of a coral reef trophic network for Qilianyu Islands,Xisha Islands显示文摘Qilianyu Islands coral reefs(QICR),located in the northeastern part of the South China Sea,has been affected by human activities and natural disturbance.To characterize the trophic structure,ecosystem properties and keystone species of this region,a food-web model for the QICR is developed using methods involving a mass-balance approach with Ecopath with Ecosim software.Trophic levels range from 1.00 for detritus and primary producers to 3.80 for chondrichthyes.The mean trophic transfer efficiency for the entire ecosystem is 13.15%,with 55%of total energy flow originating from primary producers.A mixed trophic impact analysis indicates that coral strongly impacts most components of this ecosystem.A comparison of our QICR model with that for other coral reef ecosystems suggests that the QICR ecosystem is immature and/or is degraded. | Xiaofan Hong Zuozhi Chen Jun Zhang Yan’e Jiang Yuyan Gong Yancong Cai Yutao Yang | 2022 | Acta Oceanologica Sinica2022，41，12： | 0 |
| 18 | Styrene epoxidation catalyzed by polyoxometalate/quaternary ammonium phase transfer catalysts: The effect of cation size and catalyst deactivation mechanism显示文摘Catalytic epoxidation of alkenes is an important type of organic reaction in chemical industry,and the deep insight into catalyst deactivation will help to develop new epoxidation process.In this work,series of quaternary ammoniums bearing different cationic sizes,i.e.MTOA+(methyltrioctylammonium,[(C_(8)H_(17))_(3)CH_(3)N]+),HTMA+(hexadecyltrimethylammonium,[(C_(16)H_(33))(CH_(3))_(3)N]+) and DMDOA+(dimethyldioctadecylammonium,[(C_(18)H_(37))_(2)(CH_(3))_(2)N]+) were incorporated with polyoxometalate (POM) anions to prepare phase transfer catalysts (PTCs),which were used in the styrene epoxidations.Among them,(MTOA)_(3)PW_(4)O_(24)exhibits the best catalytic performance judged from the highest styrene conversion rate(52%) and styrene oxide selectivity (93%),during which the styrene epoxidation conditions were optimized.Meanwhile,the deactivation mechanism of this kind of PTCs was proposed firstly,i.e.in the case of low H_(2)O_(2) content,the oxidant can only be used in the styrene epoxidation,in which the catalyst can transform into stable Keggin-type POM.But when the content of H_(2)O_(2) is higher,the excess H_(2)O_(2) can reactivate the Keggin-type POM into active (PW_(4)O_(24))_(3)-anions,which can trigger the ring-opening polymerization of styrene oxide.Consequently,the catalyst is deactivated by adhered poly(styrene oxide)irreversibly,which was determined by NMR spectra.In this situation,the active moiety{PO_(4)[WO(O_(2))_(2)]_(4)}_(3)-in phase-transfer catalytic system can break into some unidentified species with low W/P ratio with the presence of epoxides.This work will be beneficial for the design of new PTCs in alkene epoxidation in fine chemical industry. | Qiongna Xiao Yuyan Jiang Weiqiang Yuan Jingjing Chen Haohong Li Huidong Zheng | 2023 | Chinese Journal of Chemical Engineering2023，55，3： | 0 |
| 19 | Economic Policy Uncertainty,Heterogeneity of Executives and Enterprise Innovation显示文摘This study analyzes how economic policy uncertainty affects corporate innovation,and the moderating effects of executive heterogeneity.A threephase dynamic investment and financing model is first built to analyze the mechanism.Empirical analysis confirms that the increase in the degree of economic policy uncertainty promotes enterprise innovation.Further results show that this promotion effect is more significant in enterprises with male executives,low educational level,no financial experience and political background.Moreover,the positive impact is only found in enterprises with moderate executive ability,and the overconfidence of senior executives plays a positive regulating role in it. | Xun Han Yuyan Jiang Xianjing Huang | 2021 | Journal of Business Administration Research2021，4，3： | 0 |
| 20 | Modification on the Performance of the Hemihydrate Gypsum with the Plant Source Polymer of Dry Matcha Powder显示文摘The objective of this study was to assess the feasibility of using the plant-source polymer of the matcha powder as a composite admixture for hemihydrate gypsum. Hemihydrate gypsum was mixed with different contents of matcha powder, and then the water requirement for the normal consistency, setting times, density, strength, hydration and microstructure of the hardened mixture were evaluated. The experimental results showed that it increased the water requirement for the normal consistency, and it regulated the setting times and reduced the density. Hemihydrate gypsum with more matcha powder had the higher water requirement, longer setting times and lower density. Less than 1% matcha powder had slight impact on the strength of hardened paste, but more than 1% matcha powder had a remarkable one. Matcha powder changed the hydration process and prolonged the induction and acceleration period. Small needlelike crystals were transformed into longer, larger and thicker ones as more matcha powder was mixed. This case is closely related to the prolongation of the induction and acceleration period. Besides, more and larger pores were observed in the hardened paste with more matcha powder. It is attributed to the appearances of the tea polyphenol in matcha powder and the larger and longer crystal morphology in hardened paste as well as the high water requirement for the normal consistency. These results are important to the application of matcha powder as a composite admixture for the hemihydrate gypsum as well as the prosperity and development of the tea industry. | 李好新 XU Chao HUANG Yuyan CHEN Qing JIANG Zhengwu 王艳伟 | 2018 | Journal of Wuhan University of Technology(Materials Science)2018，33，6： | 0 |
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