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Evaluating the performance of genomic selection on purebred population by incorporating crossbred data in pigs
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作者 jun zhou Qing Lin +10 位作者 Xueyan Feng Duanyang Ren Jinyan Teng Xibo Wu Dan Wu Xiaoke Zhang Xiaolong Yuan Zanmou Chen Jiaqi Li Zhe Zhang Hao Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期639-648,共10页
Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it... Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it was limited by the purebred population.Compared to directly combining two uncorrelated purebred populations to extend the reference population size,it might be more meaningful to incorporate the correlated crossbreds into reference population for genomic prediction.In this study,we simulated purebred offspring(PAS and PBS)and crossbred offspring(CAB)base on real genotype data of two base purebred populations(PA and PB),to evaluate the performance of genomic selection on purebred while incorporating crossbred information.The results showed that selecting key crossbred individuals via maximizing the expected genetic relationship(REL)was better than the other methods(individuals closet or farthest to the purebred population,CP/FP)in term of the prediction accuracy.Furthermore,the prediction accuracy of reference populations combining PA and CAB was significantly better only based on PA,which was similar to combine PA and PAS.Moreover,the rank correlation between the multiple of the increased relationship(MIR)and reliability improvement was 0.60-0.70.But for individuals with low correlation(Cor(Pi,PA or B),the reliability improvement was significantly lower than other individuals.Our findings suggested that incorporating crossbred into purebred population could improve the performance of genetic prediction compared with using the purebred population only.The genetic relationship between purebred and crossbred population is a key factor determining the increased reliability while incorporating crossbred population in the genomic prediction on pure bred individuals. 展开更多
关键词 PIGS crossbred population genomic selection reference population construction relationship
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Targeted screening of an anti-inflammatory polypeptide from Rhopilema esculentum Kishinouye cnidoblasts and elucidation of its mechanism in alleviating ulcerative colitis based on an analysis of the gut microbiota and metabolites
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作者 Ziyan Wang Qiuyue Shi +5 位作者 Ying Feng Jiaojiao Han Chenyang Lu jun zhou Zhonghua Wang Xiurong Su 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1336-1347,共12页
Ulcerative colitis(UC)is a recurrent inflammatory bowel disease that imposes a severe burden on families and society.In recent years,exploiting the potential of marine bioactive peptides for the treatment of diseases ... Ulcerative colitis(UC)is a recurrent inflammatory bowel disease that imposes a severe burden on families and society.In recent years,exploiting the potential of marine bioactive peptides for the treatment of diseases has become a topic of intense research interest.This study revealed the mechanism underlying the protective effect of the dominant polypeptide PKKVV(Pro-Lys-Lys-Val-Val)of Rhopilema esculentum cnidoblasts against DSS-induced UC through a combined analysis of the metagenome and serum metabolome.Specifically,the polypeptide composition of R.esculentum cnidoblasts was determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF/TOF-MS).Molecular docking showed that the dominant peptide PKKVV could bind better with tumor necrosis factor-α(TNF-α)than the original ligand.Subsequent animal experiments suggested that PKKVV could modulate disorganized gut microorganisms in mice with UC;affect serum metabolites through the arachidonic acid,glycerophospholipid and linoleic acid metabolism pathways;and further alleviate UC symptoms.This study provides a reference for the comprehensive development of marine bioactive substances and nonpharmaceutical treatments for UC. 展开更多
关键词 Ulcerative colitis Rhopilema esculentum Kishinouye Cnidoblasts Marine bioactive polypeptides METAGENOME Serum metabolome
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Molecular features of gastroenteropancreatic neuroendocrine carcinoma: A comparative analysis with lung neuroendocrine carcinoma and digestive adenocarcinomas
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作者 Jianwei Zhang Hanxiao Chen +15 位作者 junli Zhang Sha Wang Yanfang Guan Wenguang Gu Jie Li Xiaotian Zhang Jian Li Xicheng Wang Zhihao Lu jun zhou Zhi Peng Yu Sun Yang Shao Lin Shen Minglei Zhuo Ming Lu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第1期90-102,共13页
Objective: There is an ongoing debate about whether the management of gastroenteropancreatic(GEP)neuroendocrine carcinoma(NEC) should follow the guidelines of small-cell lung cancer(SCLC). We aim to identify the genet... Objective: There is an ongoing debate about whether the management of gastroenteropancreatic(GEP)neuroendocrine carcinoma(NEC) should follow the guidelines of small-cell lung cancer(SCLC). We aim to identify the genetic differences of GEPNEC and its counterpart.Methods: We recruited GEPNEC patients as the main cohort, with lung NEC and digestive adenocarcinomas as comparative cohorts. All patients undergone next-generation sequencing(NGS). Different gene alterations were compared and analyzed between GEPNEC and lung NEC(LNEC), GEPNEC and adenocarcinoma to yield the remarkable genes.Results: We recruited 257 patients, including 99 GEPNEC, 57 LNEC, and 101 digestive adenocarcinomas.Among the mutations, KRAS, RB1, TERT, IL7R, and CTNNB1 were found to have different gene alterations between GEPNEC and LNEC samples. Specific genes for each site were revealed: gastric NEC(TERT amplification),colorectal NEC(KRAS mutation), and bile tract NEC(ARID1A mutation). The gene disparities between small-cell NEC(SCNEC) and large-cell NEC(LCNEC) were KEAP1 and CDH1. Digestive adenocarcinoma was also compared with GEPNEC and suggested RB1, APC, and KRAS as significant genes. The TP53/RB1 mutation pattern was associated with first-line effectiveness. Putative targetable genes and biomarkers in GEPNEC were identified in22.2% of the patients, and they had longer progression-free survival(PFS) upon targetable treatment [12.5 months vs. 3.0 months, HR=0.40(0.21-0.75), P=0.006].Conclusions: This work demonstrated striking gene distinctions in GEPNEC compared with LNEC and adenocarcinoma and their clinical utility. 展开更多
关键词 Neuroendocrine carcinoma gastroenteropancreatic LUNG genetic alterations molecular markers
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Nab-paclitaxel plus capecitabine as first-line treatment for advanced biliary tract cancers:An open-label,non-randomized,phase II clinical trial
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作者 Ling-Xiao Xu Jia-Jia Yuan +1 位作者 Ran Xue jun zhou 《World Journal of Gastroenterology》 SCIE CAS 2024年第30期3564-3573,共10页
BACKGROUND Biliary tract cancers(BTCs)are a heterogeneous group of tumors with high malignancy,poor prognosis,and limited treatment options.AIM To explore the efficacy and safety of nab-paclitaxel plus capecitabine as... BACKGROUND Biliary tract cancers(BTCs)are a heterogeneous group of tumors with high malignancy,poor prognosis,and limited treatment options.AIM To explore the efficacy and safety of nab-paclitaxel plus capecitabine as first-line treatment for advanced and metastatic BTCs.METHODS This open-label,non-randomized,double-center,phase II clinical trial recruited systemic therapy-naive patients with unresectable or metastatic BTCs between April 2019 and June 2022 at Beijing Cancer Hospital and the First Hospital of China Medical University.Eligible patients were administered nab-paclitaxel(150 mg/m^(2),day 1)and capecitabine(2000 mg/m^(2),twice daily,days 1-7)in 14-day cycles until experiencing intolerable toxicity or disease progression.The primary outcome was the objective response rate(ORR).The secondary outcomes included the disease control rate(DCR),overall survival(OS),progression-free survival(PFS),and safety.RESULTS A total of 44 patients successfully completed the trial,with a median age of 64.00 years(interquartile range,35.00-76.00),and 26(59.09%)were females.Tumor response assessment was impeded for one patient due to premature demise from tumor hemorrhage.Among the remaining 43 patients undergoing at least one imaging assessment,the ORR was 23.26%[95%confidence interval(CI):11.80%-38.60%],and the DCR was 69.77%(95%CI:53.90%-82.80%).The median OS was 14.1 months(95%CI:8.3-19.9),and the median PFS was 4.4 months(95%CI:2.5-6.3).A total of 41 patients(93.18%)experienced at least one adverse event(AE),with 10 patients(22.73%)encountering grade≥3 AEs,and the most frequent AEs of any grade were alopecia(79.50%),leukopenia(54.55%),neutropenia(52.27%),and liver dysfunction(40.91%),and no treatment-related deaths were documented.CONCLUSION Nab-paclitaxel plus capecitabine may be an effective and safe first-line treatment strategy for patients with advanced or metastatic BTCs. 展开更多
关键词 NAB-PACLITAXEL CAPECITABINE Biliary tract cancer Objective response rate Phase II clinical trial
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Clinical research on Tai Chi:a review of health benefits
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作者 Yuke Teng Weiming Luo +13 位作者 jun zhou Muchen Wang Jinghan Wu Xiaoqian Nie Cong Sun Ziyan Liang Baiyang Liu Furong Zhang Tianyu Liu Shi Zhao Fanrong Liang Xiaofan Yang Jianwei Wu Zhengjie Li 《Acupuncture and Herbal Medicine》 2024年第3期320-345,共26页
Tai Chi,a traditional Chinese martial art and health exercise,has gained significant global attention and recognition.The clinical benefits of Tai Chi have been studied extensively in recent decades.We conducted a sys... Tai Chi,a traditional Chinese martial art and health exercise,has gained significant global attention and recognition.The clinical benefits of Tai Chi have been studied extensively in recent decades.We conducted a systematic search of PubMed,Web of Science,EMBASE databases,and the China National Knowledge Infrastructure,identifying and reviewing 241 clinical trials on the benefits of Tai Chi from their inception to June 1,2023.Most of these studies have consistently demonstrated the positive impact of Tai Chi on balance,cognitive function,mood regulation,sleep quality,pain relief,cardiorespiratory function,and overall health.In the future,the key to fostering the ongoing development of this field lies in comprehensive research on standardized study designs and reporting,the scope of Tai Chi applications,and the core factors influencing its efficacy. 展开更多
关键词 Clinical trials Health-promoting effects REVIEW Tai Chi TAIJIQUAN
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Prediction and analysis of albumin-bilirubin score combined with liver function index and carcinoembryonic antigen on liver metastasis of colorectal cancer
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作者 Zhan-Mei Wang Shu-Ping Pan +1 位作者 Jing-Jing Zhang jun zhou 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1670-1680,共11页
BACKGROUND Colorectal cancer(CRC)is a common malignant tumor,and liver metastasis is one of the main recurrence and metastasis modes that seriously affect patients’survival rate and quality of life.Indicators such as... BACKGROUND Colorectal cancer(CRC)is a common malignant tumor,and liver metastasis is one of the main recurrence and metastasis modes that seriously affect patients’survival rate and quality of life.Indicators such as albumin bilirubin(ALBI)score,liver function index,and carcinoembryonic antigen(CEA)have shown some potential in the prediction of liver metastasis but have not been fully explored.AIM To evaluate its predictive value for liver metastasis of CRC by conducting the combined analysis of ALBI,liver function index,and CEA,and to provide a more accurate liver metastasis risk assessment tool for clinical treatment guidance.METHODS This study retrospectively analyzed the clinical data of patients with CRC who received surgical treatment in our hospital from January 2018 to July 2023 and were followed up for 24 months.According to the follow-up results,the enrolled patients were divided into a liver metastasis group and a nonliver metastasis group and randomly divided into a modeling group and a verification group at a ratio of 2:1.The risk factors for liver metastasis in patients with CRC were analyzed,a prediction model was constructed by least absolute shrinkage and selection operator(LASSO)logistic regression,internal validation was performed by the bootstrap method,the reliability of the prediction model was evaluated by subject-work characteristic curves,calibration curves,and clinical decision curves,and a column graph was drawn to show the prediction results.RESULTS Of 130 patients were enrolled in the modeling group and 65 patients were enrolled in the verification group out of the 195 patients with CRC who fulfilled the inclusion and exclusion criteria.Through LASSO regression variable screening and logistic regression analysis.The ALBI score,alanine aminotransferase(ALT),and CEA were found to be independent predictors of liver metastases in CRC patients[odds ratio(OR)=8.062,95%confidence interval(CI):2.545-25.540],(OR=1.037,95%CI:1.004-1.071)and(OR=1.025,95%CI:1.008-1.043).The area under the receiver operating characteristic curve(AUC)for the combined prediction of CRLM in the modeling group was 0.921,with a sensitivity of 78.0%and a specificity of 95.0%.The H-index was 0.921,and the H-L fit curve hadχ^(2)=0.851,a P value of 0.654,and a slope of the calibration curve approaching 1.This indicates that the model is extremely accurate,and the clinical decision curve demonstrates that it can be applied effectively in the real world.We conducted internal verification of one thousand resamplings of the modeling group data using the bootstrap method.The AUC was 0.913,while the accuracy was 0.869 and the kappa consistency was 0.709.The combination prediction of liver metastasis in patients with CRC in the verification group had an AUC of 0.918,sensitivity of 85.0%,specificity of 95.6%,C-index of 0.918,and an H-L fitting curve withχ^(2)=0.586,P=0.746.CONCLUSION The ALBI score,ALT level,and CEA level have a certain value in predicting liver metastasis in patients with CRC.These three criteria exhibit a high level of efficacy in forecasting liver metastases in patients diagnosed with CRC.The risk prediction model developed in this work shows great potential for practical application. 展开更多
关键词 Albumin-bilirubin Carcinoembryonic antigen Colorectal cancer Tumor metastasis Prediction model
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Phylogeography and Cryptic Species Diversity of Paramesotriton caudopunctatus Species Group(Salamandridae: Paramesotriton) in Guizhou, China 被引量:2
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作者 Tao LUO Huamei WEN +2 位作者 Kai GAO jun zhou Jiang zhou 《Asian Herpetological Research》 SCIE CSCD 2021年第2期188-200,共13页
The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary rel... The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary relationships and divergence-time of members of this species group as a whole remain unexplored. In this study, we report the sequencing of one protein coding mitochondrial gene fragment(ND2) and one nuclear gene(POMC), and use a combination of phylogenetic analyses and coalescent simulations to explore the cryptic diversity and evolutionary history of the P. caudopunctatus species group. Phylogenetic relationships revealed that the P. caudopunctatus species group is composed of two major groups, i. e., East Clade and Western-South Clade. The divergence-time and ancestral area estimation suggested that the P. caudopunctatus species group likely originated in the Doupeng Mountains in Guizhou, China at 12.34 Ma(95% HPD: 8.30–14.73), and intraspecific divergence began at about 2.17 Ma(95% HPD: 1.39–2.97). This timing coincides with the orogenesis of the Miaoling Mountains during the Late Miocene to early Pleistocene. The delimitation of species in the P. caudopunctatus species group supports the existence of the currently identified species, and consensus was confirmed across methods for the existence of least to two cryptic species within what has been traditionally considered to be P. caudopunctatus species group. This study is of significance for understanding the species formation, dispersal, and diversity of the tailed amphibians in the karst mountains ecosystem of Guizhou and the role of the Miaoling Mountains as a geographical barrier to species dispersal. 展开更多
关键词 P.caudopunctatus species group PHYLOGEOGRAPHY cryptic diversity BIOGEOGRAPHY species delimitation GUIZHOU
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A NEW CYCLOPEPTIDE FROM ARENARIA JUNCEA 被引量:2
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作者 Yu Rui ZHAO jun zhou +3 位作者 Xian Kai WANG Xiao Lin HUANG Hou Ming WU Tong Fang ZHAO(Department of Medicinal Chemistry of Natural Products, School of Pharmacy, West China University of Medical Sciences. Chengdu, 610041)(Laboratory of Phytochemistry, Kunming I 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第9期751-754,共4页
A new cyclopeptide named arenarin A(1) was obtained from the roots of Arenaria juncea Bieb and its structure was established to be cyclo(Ser-Ser-Phe-lle-Pro-Phe)by a combination of 2D-NMR and FABMS.
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Feasibility Study of Enforcing Immunization Certificate Check Before Primary School or Kindergarten Enrollment in Guizhou Province, China
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作者 LI SHENG SHU-YAN ZUO +8 位作者 JING XIE YA-LI QI YI-BING TONG GUANG-PENG TANG jun zhou DA-YONG ZHANG CHANG-BING LONG WEN DU ZI-JIAN FENG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第5期357-365,共9页
Objective To study the feasibility of enforcing immunization certificate check before children enroll in primary schools or kindergartens in Guizhou Province. Methods Quantitative and qualitative studies were conducte... Objective To study the feasibility of enforcing immunization certificate check before children enroll in primary schools or kindergartens in Guizhou Province. Methods Quantitative and qualitative studies were conducted. The multi-stage and cluster sampling approach was adopted for the quantitative part of the study. A questionnaire was designed and 996 children and their keepers were interviewed. Principals, doctors or teachers of the primary schools, directors and child care nurses of kindergarten, and staff of immunization agencies were invited to take part in 12 focus group discussions; meanwhile, face-to-face individual in-depth interviews with 16 officials of the Health, Education and Governmental Departments at various levels were conducted. Results The total number of subjects was 996. 16.7% of the children in the study completed all the procedures of the National Immunization Programme. 34.3% of them had immunization certificates while the remainder 44.7% registered in immunization agencies. Factors, including the migrant children, doubt about vaccine efficiency, mother’s occupation and educational background, knowledge of the National Immunization Programme on targeted vaccines, played an important role in obtaining or not immunization certificates. 95% of the keepers interviewed thought the immunization certificates were useful; 94.8% of them considered the check was critical while only 3.6% of them thought it unnecessary. The first reason from those who found it unnecessary was that they feared that repeated immunization might affect their children’s health. The second reason was the cost of immunization, which some of them could not afford to pay. However, the Health Department expressed a favorable attitude to the checking scheme. Though the Education Department agreed that the scheme was essential, they worried that it would affect the enrollment rate.Conclusion In spite of the difficulty in administering immunization certificate check, the effort would be rewarding for raising the immunization coverage rate among the children in Guizhou Province. 展开更多
关键词 Immunization certificate check Impacting factors Sampling research Quantitative study Qualitative study Enrollment rate
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闪速吹炼炉内颗粒在不同操作参数下的分布与演化规律
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作者 祝振宇 周萍 +4 位作者 陈卓 周俊 万兴邦 张劲松 任鹏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第9期2866-2878,共13页
通过开展工业试验揭示闪速吹炼炉内颗粒质量和粒径的分布与演化规律,同时研究不同配风参数对颗粒分布的影响。结果表明,颗粒在反应塔内的下落过程中,其平均粒径增长通常为2~3倍,且聚并后的大颗粒主要分布在料锥中部和外部;而导致该现象... 通过开展工业试验揭示闪速吹炼炉内颗粒质量和粒径的分布与演化规律,同时研究不同配风参数对颗粒分布的影响。结果表明,颗粒在反应塔内的下落过程中,其平均粒径增长通常为2~3倍,且聚并后的大颗粒主要分布在料锥中部和外部;而导致该现象出现的原因是较高的湍流强度和颗粒分布密度、以及天然气燃烧的位置使该位置处颗粒升温熔融、并发生碰撞和聚并。另外,提高分散风与工艺风动量比能使物料颗粒在反应塔内的分布更加均匀,更有利于冰铜的氧化反应。相较于调整工艺风参数,改变分散风能更有效地提高颗粒的空间分布范围。 展开更多
关键词 工业试验 颗粒演化 质量分布 粒径分布 动量比 闪速吹炼炉
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丁羟推进剂药浆流平性能实验与模拟
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作者 周君 李卓 +2 位作者 鲁荣 魏凌云 张芙宁 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第4期85-92,共8页
为研究表观黏度及屈服应力对丁羟推进剂药浆流平性的影响,文中对丁羟推进剂药浆进行了流平性实验,并提出滞止角的概念来表征药浆的流平性,得出药浆屈服应力对滞止角的影响规律。同时采用Carreau黏度模型模拟了药浆流平过程并与实验结果... 为研究表观黏度及屈服应力对丁羟推进剂药浆流平性的影响,文中对丁羟推进剂药浆进行了流平性实验,并提出滞止角的概念来表征药浆的流平性,得出药浆屈服应力对滞止角的影响规律。同时采用Carreau黏度模型模拟了药浆流平过程并与实验结果进行了对比,并通过计算软件Flow3D定量表征了丁羟推进剂药浆的表观黏度、屈服应力单变量对流平性的影响。结果表明,丁羟推进剂药浆的流动角度与药浆流平时间的对数满足线性关系;不同时刻药浆流动角度的数值模拟与实验结果误差在5%以内,内侧流到终点的时间相差小于10%,验证了Carreau黏度模型求解药浆流平过程的可行性。丁羟推进剂药浆的表观黏度是影响流平速度的主要参数,当表观黏度由400 Pa·s增大到1000 Pa·s时,药浆流平所需时间由277s延长到871s;屈服应力决定了药浆流平结束时滞止角的大小,当屈服应力由60Pa增大到120Pa时,滞止角由8.69°增大到14.98°,相应增加了72.4%。 展开更多
关键词 固体推进剂 药浆 表观黏度 屈服应力 流平性
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振动激励对丁羟推进剂药浆流平性影响的实验与数值模拟
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作者 周君 李卓 +1 位作者 张芙宁 魏凌云 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第10期91-98,共8页
为研究振动激励对丁羟推进剂药浆流平性的影响机理,利用可视化实验装置对丁羟推进剂药浆进行了自然流平与振动流平实验,并将实验结果进行了定量化对比分析;利用旋转流变仪对丁羟推进剂药浆进行了流变特性测试,并以测试结果为输入,用Carr... 为研究振动激励对丁羟推进剂药浆流平性的影响机理,利用可视化实验装置对丁羟推进剂药浆进行了自然流平与振动流平实验,并将实验结果进行了定量化对比分析;利用旋转流变仪对丁羟推进剂药浆进行了流变特性测试,并以测试结果为输入,用Carreau黏度模型对药浆流平过程进行了数值模拟。结果表明,振动激励可以有效缩短药浆的流平时间;丁羟推进剂药浆是屈服假塑性流体,在一定剪切速率范围内,黏度随剪切速率的增大而减小,振动激励能将药浆流平过程中的剪切速率维持在较高水平,从而使振动流平实验中药浆的黏度相对较低,明显改善了药浆的流动性;与自然流平时间相比,在振动激励作用下,药浆流平时间缩短了51%;丁羟推进剂药浆流平过程的数值模拟与实验结果误差在10%以内,验证了Carreau黏度模型求解药浆流平过程的可行性。 展开更多
关键词 固体推进剂 药浆 振动 流平性
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丁羟推进剂药浆可视化浇注试验及缺陷数值模拟
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作者 周君 李卓 鲁荣 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第6期111-118,共8页
采用可视化真空花板浇注装置对固体发动机进行浇注实验,研究浇注过程中药浆的流动状态及产生气孔的变化规律。利用Carreau模型对浇注过程中出现的不同大小、位置的气孔进行模拟计算,得出不同条件下气孔的变化规律,并将仿真结果与试验进... 采用可视化真空花板浇注装置对固体发动机进行浇注实验,研究浇注过程中药浆的流动状态及产生气孔的变化规律。利用Carreau模型对浇注过程中出现的不同大小、位置的气孔进行模拟计算,得出不同条件下气孔的变化规律,并将仿真结果与试验进行了对比分析。结果表明,浇注过程中药浆堆积表面不平整,药浆先在发动机底部花板对应区域堆积一定高度后再流向四周,最终在重力作用下逐渐压实、流平;在自由液面附近贴近壳体的位置会出现大量的气孔,气孔的形成位置和形态都具有随机性;通常气孔都会先由不规则形状向近似圆形过渡再逐渐变小,并最终在一定压力作用下经过流平后逐渐消失;近似圆形气孔的存在时间与气孔直径有较大相关性,气孔直径越大,消失所需时间越长;相同大小的气孔在不同位置存在的时间亦有差异,底角位置气孔存在时间相对长,其次为贴近壳体位置,在药浆内部的气孔存在时间最短;对气孔消失过程的数值模拟与实验结果误差在20%以内,验证了Carreau黏度模型求解推进剂药浆中气孔变化过程的可行性。实验中产生的气孔经过药浆流平后最终均消失,固体推进剂完整性良好。 展开更多
关键词 丁羟推进剂 药浆 浇注 气孔
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铜闪速熔炼渣中砷的赋存状态和浸出毒性 被引量:1
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作者 张惠斌 王亚楠 +6 位作者 朱殷斌 任鹏 胡彬 徐圣航 曹华珍 周俊 郑国渠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第1期293-303,共11页
铜冶炼含砷炉渣的高效安全处置取决于对其含砷物相及其浸出毒性的准确认识。采用X射线荧光光谱、X射线衍射、电子探针显微分析、扫描电子显微术和选择性逐级提取法对铜熔炼渣中的含砷物相进行鉴定,并基于对炉渣中不同含砷物相的选择性... 铜冶炼含砷炉渣的高效安全处置取决于对其含砷物相及其浸出毒性的准确认识。采用X射线荧光光谱、X射线衍射、电子探针显微分析、扫描电子显微术和选择性逐级提取法对铜熔炼渣中的含砷物相进行鉴定,并基于对炉渣中不同含砷物相的选择性逐级提取结果探讨渣中砷浸出毒性的可能来源。结果表明,砷以水溶性砷、铜砷金属间化合物、铜砷硫化物以及固化在铁橄榄石和硅酸盐玻璃相中的砷等形式赋存在熔炼渣中。浮选过程可以去除熔炼渣中的水溶性砷并回收铜砷金属间化合物,降低渣尾矿的砷浸出毒性,使其符合USEPA和SEPA标准要求。 展开更多
关键词 铜闪速熔炼 铜炉渣 选择性逐级提取 浸出毒性
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Tuning exsolution of nanoparticles in defect engineered layered perovskite oxides for efficient CO_(2) electrolysis 被引量:1
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作者 Zhengrong Liu jun zhou +7 位作者 Yueyue Sun Xiangling Yue Jiaming Yang Lei Fu Qinyuan Deng Hongfei Zhao Chaofan Yin Kai Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期219-227,共9页
Solid oxide electrolysis cell(SOEC) could be a potential technology to afford chemical storage of renewable electricity by converting water and carbon dioxide.In this work,we present the Ni-doped layered perovskite ox... Solid oxide electrolysis cell(SOEC) could be a potential technology to afford chemical storage of renewable electricity by converting water and carbon dioxide.In this work,we present the Ni-doped layered perovskite oxides,(La_(4)Sr_(n-4))_(0.9)Ti_(0.9n)Ni_(0.1n)O_(3n+2) with n=5,8,and 12(LSTNn) for application as catalysts of CO_(2) electrolysis with the exsolution of Ni nanoparticles through a simple in-situ growth method.It is found that the density,size,and distribution of exsolved Ni nanoparticles are determined by the number of n in LSTNn due to the different stack structures of TiO_6 octahedra along the c axis.The Ni doping in LSTNn significantly improved the electrochemical activity by increasing oxygen vacancies,and the Ni metallic nanoparticles afford much more active sites.The results show that LSTNn cathodes can successfully be manipulated the activity by controlling both the n number and Ni exsolution.Among these LSTNn(n=5,8,and 12),LSTN8 renders a higher activity for electrolysis of CO_(2) with a current density of 1.50A cm^(-2)@2.0 V at 800℃ It is clear from these results that the number of n in(La_(4)Sr_(n-4))_(0.9)Ti_(0.9n)Ni_(0.1n)O_(3n+2)with Ni-doping is a key factor in controlling the electrochemical performance and catalytic activity in SOEC. 展开更多
关键词 Layered perovskite oxides In-situ growth SOEC TITANATE
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Laboratory study of the factors affecting hydraulic fracturing effect for inter-salt oil shale layers,Qianjiang Depression,China
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作者 jun zhou Guang-Ai Wu +4 位作者 Ya-Nan Geng Yin-Tong Guo Xin Chang Cheng-Yong Peng Chuan-Zhi Ai 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1690-1706,共17页
This study aims to investigate the potential factors affecting hydraulic fracturing of inter-salt oil shale reservoirs in the Qianjiang Depression,China.Using the inter-salt shale samples,the re-crystallization seepag... This study aims to investigate the potential factors affecting hydraulic fracturing of inter-salt oil shale reservoirs in the Qianjiang Depression,China.Using the inter-salt shale samples,the re-crystallization seepage tests,rock mechanical tests under high temperature and pressure,salt rock creep tests,and direct shear tests were conducted.The testing results suggest several major factors that affect hydraulic fracturing effects in the end.First,the seepage of reservoir and fracturing fluid through hydraulic frac-tures leads to salt dissolution and crystallization,reducing the effective seepage area of fractures.Second,the salt crystal may block the pore throats or micro fractures after brine invades the shale,decreasing the overall permeability.Third,the low strength and obvious plasticity of inter-salt shale and the strong creep characteristics of salt rock raise difficulties for proppant to effectively support fracture walls,thereby sharply narrowing the hydraulic fracture width.Lastly,the weak interfaces(bedding planes and lithology interfaces)in inter-salt oil shale reservoirs restrict the height of hydraulic fractures,resulting in the disconnection of seepage channels between multiple inter-salt shale reservoirs.Thus,several factors together reduce reservoir permeability,weaken the fluid flow capacity in the fracture,narrow the fracture width,and limit the effective stimulation volume,resulting in weaken the effect hydraulic fracturing. 展开更多
关键词 Shale oil Salt rock Qianjiang Depression Hydraulic fracturing RECRYSTALLIZATION
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Effect of Cu addition on the microstructure and tribological performance of Ni60 directional structure coating
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作者 Xiaotian Yang Xinhua Wang +3 位作者 jun zhou Hengli Wei Rong Zeng Wensheng Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第4期715-723,共9页
The Ni60/15wt% Cu directional structure coating was prepared by the composite technology of flame spraying, induction remelting,and forced cooling, and the effect of Cu on the microstructure, phase, hardness, and wear... The Ni60/15wt% Cu directional structure coating was prepared by the composite technology of flame spraying, induction remelting,and forced cooling, and the effect of Cu on the microstructure, phase, hardness, and wear performance of Ni60 coatings was investigated. Results showed that Cu addition makes the microstructure of Ni60 directional structure coating more compact, and Cu is mainly enriched within the crystal grain, resulting in the formation of Cu_(3.8)Ni as the bonding phase. Compared with Ni60 directional structure coating, Ni60/Cu directional structure coating has a lower hardness, lower friction coefficient, and lower wear rate, which indicate that Cu can effectively enhance the antifriction performance of Ni60 directional structure coating. 展开更多
关键词 induction remelting directional structure coating MICROSTRUCTURE tribological performance
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Multi-band polarization switch based on magnetic fluid filled dual-core photonic crystal fiber
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作者 张连震 张学典 +5 位作者 俞宪同 刘学静 周军 常敏 杨娜 杜嘉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期286-292,共7页
The research of high-performance polarization controllers is of great significance for expanding the application field of polarization optics. Here, a polarization switch is demonstrated by using a dual-core photonic ... The research of high-performance polarization controllers is of great significance for expanding the application field of polarization optics. Here, a polarization switch is demonstrated by using a dual-core photonic crystal fiber(DCPCF)with four symmetrical air holes, placed above and below each core, filled with magnetic fluid(MF). The switch, which utilizes a magnetic field to change the coupling length ratio of the x and y polarization modes, enables dynamic tuning of the polarization state and extinction ratio. Numerical results show that when the working length is 36.638 mm, the magneto–optical polarization switch can operate in four communication bands, i.e., 1509 nm to 1520 nm, 1544 nm to1556 nm, 1578 nm to 1591 nm, and 1611 nm to 1624 nm. Moreover, the extinction ratio(ER) is greater than 20 d B in the fiber length range of 38.5 mm to 38.7 mm, indicating that the device has a good fault tolerance for the interception of the fiber length. 展开更多
关键词 polarization switch magnetic fluid dual-core photonic crystal fiber
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Hydrophobic Small-Molecule Polymers as High-Temperature-Resistant Inhibitors in Water-Based Drilling Fluids
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作者 Xuyang Yao Kecheng Liu +5 位作者 Zenan zhou jun zhou Xianbin Huang Tiemei Lu Yongsheng Yu He Li 《Fluid Dynamics & Materials Processing》 EI 2023年第7期1775-1787,共13页
Water-based drilling fluids can cause hydration of the wellbore rocks,thereby leading to instability.This study aimed to synthesize a hydrophobic small-molecule polymer(HLMP)as an inhibitor to suppress mud shale hydra... Water-based drilling fluids can cause hydration of the wellbore rocks,thereby leading to instability.This study aimed to synthesize a hydrophobic small-molecule polymer(HLMP)as an inhibitor to suppress mud shale hydration.An infrared spectral method and a thermogravimetric technique were used to characterize the chemical composition of the HLMP and evaluate its heat stability.Experiments were conducted to measure the linear swelling,rolling recovery rate,and bentonite inhibition rate and evaluate accordingly the inhibition performance of the HLMP.Moreover,the HLMP was characterized through measurements of the zeta potential,particle size distribution,contact angles,and interlayer space testing.As confirmed by the results,the HLMP could successfully be synthesized with a favorable heat stability.Furthermore,favorable results were found for the inhibitory processes of the HLMP on swelling and dispersed hydration during mud shale hydration.The positively charged HLMP could be electrically neutralized with clay particles,thereby inhibiting diffusion in the double electron clay layers.The hydrophobic group in the HLMP molecular structure resulted in the formation of a hydrophobic membrane on the rock surface,enhancing the hydrophobicity of the rock.In addition,the small molecules of the HLMP could plug the spaces between the layers of bentonite crystals,thereby reducing the entry of water molecules and inhibiting shale hydration. 展开更多
关键词 Water-based drilling fluids hydrophobic polymers shale inhibitor temperature resistance
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ERF5.1 modulates carotenoid accumulation by interacting with CCD4.1 in Lycium
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作者 Jianhua Zhao Yuhui Xu +13 位作者 Haoxia Li Xinlei Zhu Yue Yin Xiyan Zhang Xiaoya Qin jun zhou Linyuan Duan Xiaojie Liang Ting Huang Bo Zhang Ru Wan Zhigang Shi Youlong Cao Wei An 《Horticulture Research》 SCIE CSCD 2023年第12期190-203,共14页
Carotenoids are important natural pigments and have medical and health functions for humans.Carotenoid cleavage dioxygenase 4(CCD4)and ethylene responsive factor(ERF)participate in carotenoid metabolism,but their role... Carotenoids are important natural pigments and have medical and health functions for humans.Carotenoid cleavage dioxygenase 4(CCD4)and ethylene responsive factor(ERF)participate in carotenoid metabolism,but their roles in Lycium have not been discovered.Here,we annotated LbCCDs from the Lycium reference genome and found that LbCCD4.1 expression was significantly correlated with the carotenoid metabolites during Lycium five fruit developmental stages.Over-expression of LbCCD4.1 in NQ’s leaves resulted in a series of significantly lower contents of carotenoid metabolites,includingβ-carotene andβ-cryptoxanthin.Moreover,LbERF5.1,a transcription factor belonging to the ERF family that was located in the nucleus,was isolated.Significant reductions in the carotenoids,especially lutein,violaxanthin and their derivatives,were observed in over-expressing ERF5.1 transgenic NQ’s leaves.Over-expression or virus-induced gene silencing of LbERF5.1 in NQ’s leaves induced a consistent up-or down-expression,respectively,of LbCCD4.1.Furthermore,yeast one-hybrid and dual-luciferase reporter assays showed that ERF5.1 interacted with the promoter of CCD4.1 to increase its expression,and LbERF5.1 could bind to any one of the three predicted binding sites in the promoter of LbCCD4.1.A transcriptome analysis of LbERF5.1 and LbCCD4.1 over-expressed lines showed similar global transcript expression,and geranylgeranyl diphosphate synthase,phytoene synthase,lycopeneδ-cyclase cytochrome,cytochrome P450-type monooxygenase 97A,cytochrome P450-type monooxygenase 97C,and zeaxanthin epoxidase in the carotenoid biosynthesis pathway were differentially expressed.In summary,we uncovered a novel molecular mechanism of carotenoid accumulation that involved an interaction between ERF5.1 and CCD4.1,which may be used to enhance carotenoid in Lycium. 展开更多
关键词 METABOLISM EXPRESSING LYCIUM
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