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固溶时间对Ti@(Al-Si-Ti)_(p)/A356复合材料组织及力学性能的影响

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热加工工艺 2024年第6期53卷 21-25页

作者：张金玉陈体军兰州理工大学材料科学与工程学院甘肃兰州73050 兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室甘肃兰州73050 陕西柴油机重工有限公司陕西兴平713105

采用粉末触变成形技术制备了原位自生心-壳结构增强A356铝基复合材料,并研究了固溶时间对Ti@(Al-Si-Ti)_(p)/A356复合材料显微其组织及力学性能的影响。结果表明,随着固溶时间增加,初生α-Al相颗粒粗化长大;共晶Si相不断溶解,晶界上残... 详细信息

采用粉末触变成形技术制备了原位自生心-壳结构增强A356铝基复合材料,并研究了固溶时间对Ti@(Al-Si-Ti)_(p)/A356复合材料显微其组织及力学性能的影响。结果表明,随着固溶时间增加,初生α-Al相颗粒粗化长大;共晶Si相不断溶解,晶界上残余的共晶Si粗化、球状化;Al基体、Ti心部继续反应,增强体颗粒壳层发生相转变。复合材料在545℃固溶处理1 h时,力学性能达到峰值,其抗拉强度、屈服强度和伸长率分别为263.9 MPa、175.1 MPa、20%,比制备态复合材料分别提高了7.3%、21.4%和12.4%,维氏硬度也从59.3 hV提高到72.8 hV。

关键词：粉末触变成形 Ti@(Al-Si-Ti)_(p)/A356复合材料固溶时间力学性能

Predicting short-term thromboembolic risk following Roux-en-Y gastric bypass using supervised machine learning

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1097-1108页

作者： hassam Ali Faisal Inayat Vishali Moond Ahtshamullah Chaudhry Arslan Afzal Zauraiz Anjum hamza Tahir Muhammad Sajeel Anwar Dushyant Singh Dahiya Muhammad Sohaib Afzal Gul Nawaz Amir h Sohail Muhammad Aziz Department of Gastroenterology East Carolina University Brody School of MedicineGreenvilleNC 27834United States Department of Internal Medicine Allama Iqbal Medical CollegeLahorePunjab 54550Pakistan Department of Internal Medicine Saint Peter's University Hospital and Robert Wood Johnson Medical SchoolNew BrunswickNJ 08901United States Department of Internal Medicine St.Dominic's HospitalJacksonMS 39216United States Department of Internal Medicine Rochester General HospitalRochesterNY 14621United States Department of Internal Medicine Jefferson Einstein HospitalPhiladelphiaPA 19141United States Department of Internal Medicine UHS Wilson Medical CenterJohnsonNY 13790United States Division of Gastroenterology Hepatology and MotilityThe University of Kansas School of MedicineKansasKS 66160United States Department of Internal Medicine Louisiana State University HealthShreveportLA 71103United States Department of Surgery University of New Mexico School of MedicineAlbuquerqueNM 87106United States Department of Gastroenterology and hepatology The University of ToledoToledoOH 43606United States

BACKGROUND Roux-en-Y gastric bypass(RYGB)is a widely recognized bariatric procedure that is particularly beneficial for patients with class III *** aids in significant weight loss and improves obesity-related medical *** its effectiveness,postoperative care still has *** evidence shows that venous thromboembolism(VTE)is a leading cause of 30-d morbidity and mortality after ***,a clear unmet need exists for a tailored risk assessment tool for VTE in RYGB *** To develop and internally validate a scoring system determining the individualized risk of 30-d VTE in patients undergoing *** Using the 2016–2021 Metabolic and Bariatric Surgery Accreditation Quality Improvement Program,data from 6526 patients(body mass index≥40 kg/m^(2))who underwent RYGB were analyzed.A backward elimination multivariate analysis identified predictors of VTE characterized by pulmonary embolism and/or deep venous thrombosis within 30 d of *** resultant risk scores were derived from the coefficients of statistically significant *** performance of the model was evaluated using receiver operating curves through 5-fold *** Of the 26 initial variables,six predictors were *** included a history of chronic obstructive pulmonary disease with a regression coefficient(Coef)of 2.54(Pength of stay(Coef 0.08,Penous thrombosis(Coef 1.61,Phemoglobin A1c>7%(Coef 1.19,Penous stasis history(Coef 1.43,Phese variables were weighted according to their regression coefficients in an algorithm that was generated for the model predicting 30-d VTE risk *** risk model's area under the curve(AUC)was 0.79[95%confidence interval(CI):0.63-0.81],showing good discriminatory power,achieving a sensitivity of 0.60 and a specificity of *** training,the same model performed satisfactorily

关键词： Roux-en-Y gastric bypass Venous thromboembolism Machine learning Bariatric surgery Predictive modeling

稳定化退火温度对5059铝合金冷轧板材组织及性能的影响

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东北大学学报（自然科学版） 2024年第3期45卷 323-330页

作者：朱庆丰黄建航高扬张恩阁东北大学材料电磁过程研究教育部重点实验室辽宁沈阳110819 东北大学材料先进制备技术教育部工程研究中心辽宁沈阳110819 东北大学材料科学与工程学院辽宁沈阳110819

对5059铝合金冷轧板材进行了不同温度(125~275℃)保温1 h的稳定化退火处理,研究了稳定退火温度对板材组织性能的影响.研究结果表明:变形量为62.8%冷轧板材的变形组织内形成了穿过多个纤维状晶粒的剪切带;板材经不同温度(150~225℃)保温... 详细信息

对5059铝合金冷轧板材进行了不同温度(125~275℃)保温1 h的稳定化退火处理,研究了稳定退火温度对板材组织性能的影响.研究结果表明:变形量为62.8%冷轧板材的变形组织内形成了穿过多个纤维状晶粒的剪切带;板材经不同温度(150~225℃)保温1 h退火后,沿剪切带析出连续的β相,这些板材在晶间腐蚀过程中沿着剪切带形成了腐蚀沟壑.随着退火温度由125°C升高至275℃,5059铝合金冷轧板材的屈服强度和抗拉强度分别由386,474 MPa降低至301,407 MPa;延伸率则由10.4%升高到18.1%.5059铝合金冷轧板材单位面积内腐蚀量则先由125℃×1 h退火板材的13.7 mg/cm^(2),升至200℃×1 h退火板材的53.8 mg/cm^(2),再逐渐降至275℃×1 h退火板材的4.9 mg/cm^(2).

关键词： 5059铝合金轧制稳定化退火晶间腐蚀拉伸性能

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Recent Ventures in Interdisciplinary Arctic Research:The ARCPATh Project

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Advances in Atmospheric Sciences 2024年第8期41卷 1559-1568页

作者： Astrid E.J.OGILVIE Leslie A.KING Noel KEenLYSIDE François COUNILLON Brynhildur DAVIÐSDÓTTIR Níels EINARSSON Sergey GULEV Ke FAN Torben KOenIGK James R.MCGOODWIN Marianne h.RASMUSSON Shuting YANG Institute of Arctic and Alpine Research(INSTAAR) University of ColoradoBoulder CO 80303USA Stefansson Arctic Institute AkureyriÍS-600Iceland Royal Roads University BC V9B 5Y2Canada University of Bergen Bergen N-5007Norway Nansen environmental and Remote Sensing Centre Bergen N-5007Norway University of Iceland Reykjavík 102Iceland Shirshov Institute of Oceanology Moscow 117218Russia Moscow State University Moscow 11991Russia Chinese Academy of Sciences Beijing 100045China Swedish Meteorological and hydrological Institute SE-60176 NorrköpingSweden Danish Meteorological Institute CopenhagenØ2100Denmark Obukhov Institute of Atmospheric Physics RAS119017MoscowRussia

This paper celebrates Professor Yongqi GAO's significant achievement in the field of interdisciplinary studies within the context of his final research project Arctic Climate Predictions: Pathways to Resilient Sustainable Societies-ARCPATh(https://***/en/projects/finished-projects/arcpath). The disciplines represented in the project are related to climatology, anthropology, marine biology, economics, and the broad spectrum of social-ecological studies. Team members were drawn from the Nordic countries, Russia, China, the United States, and Canada. The project was transdisciplinary as well as interdisciplinary as it included collaboration with local knowledge holders. ARCPATh made significant contributions to Arctic research through an improved understanding of the mechanisms that drive climate variability in the Arctic. In tandem with this research, a combination of historical investigations and social, economic, and marine biological fieldwork was carried out for the project study areas of Iceland, Greenland, Norway, and the surrounding seas, with a focus on the joint use of ocean and sea-ice data as well as social-ecological drivers. ARCPATh was able to provide an improved framework for predicting the near-term variation of Arctic climate on spatial scales relevant to society, as well as evaluating possible related changes in socioeconomic realms. In summary, through the integration of information from several different disciplines and research approaches, ARCPATh served to create new and valuable knowledge on crucial issues, thus providing new pathways to action for Arctic communities.

关键词： Recent Ventures in Interdisciplinary Arctic Research:The ARCPATh Project

基于拉曼光谱与色度学的彩色淡水有核珍珠研究

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光谱学与光谱分析 2024年第6期44卷 1684-1688页

作者：王子轩杨淼柳迪文孟彬祖恩东昆明理工大学材料科学与工程学院云南昆明650093

淡水有核珍珠因为其粒径大、圆度好、色彩丰富、光泽强等优点,在珍珠市场上占据了较大份额。目前关于彩色淡水有核珍珠的致色机理尚没有一致的结论,且关于该致色物质如何使淡水有核珍珠呈现多种颜色的研究较少。基于此研究现状,选取多... 详细信息

淡水有核珍珠因为其粒径大、圆度好、色彩丰富、光泽强等优点,在珍珠市场上占据了较大份额。目前关于彩色淡水有核珍珠的致色机理尚没有一致的结论,且关于该致色物质如何使淡水有核珍珠呈现多种颜色的研究较少。基于此研究现状,选取多种颜色的淡水有核珍珠进行激光拉曼光谱与色度学研究。拉曼光谱研究发现样品具有三种不同的C—C与C C峰,且表现出对应关系:1123~1125 cm^(-1)处的C—C峰常与1506~1509 cm^(-1)处的C C峰同时出现;1132~1134 cm^(-1)处的C—C峰常与1522~1523或1525 cm^(-1)处的C C峰同时出现;1128~1131 cm^(-1)处的C—C峰常与1506~1509与1520~1523或1525 cm^(-1)的C C双重峰同时出现。依据拉曼光谱中C C键峰的差异将全部样品分为P、T、G、P+T、T+G、P+G共6种类型。结合样品的色度学参数,在同类型样品中,建立亮度L或饱和度S与其拉曼光谱中CO_(3)/C—C峰面积比的相关性,发现P型珠的亮度L与CO_(3)/C—C峰面积比有明显的正相关性,而P、T、G型珠的饱和度S都与CO_(3)/C—C峰面积比有明显的负相关性,证实三种不同的C—C与C C峰是由不同的致色物质所致。并根据拉曼谱峰将彩色淡水有核珍珠中的致色有机物归属为线性多烯类分子。线性多烯分子的拉曼峰位随着有序度的增加而红移,拉曼峰位更靠近红外区的线性多烯分子的碳骨架更长更直,这导致不同类型样品的拉曼光谱中C—C与C C的峰有所区别。此外,依据色度学参数对彩色淡水有核珍珠进行颜色系列的划分。将色调角h∈(0,15)的珍珠归为红色系列;将色调角h∈(15,45)的珍珠归为黄色系列;将色调角h∈(335,360)的珍珠归为紫色系列。

关键词：淡水有核珍珠拉曼光谱色度学峰面积比线性多烯

介孔氮化碳负载钒催化氧化四氢糠醇制备γ-丁内酯

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石油化工应用 2024年第2期43卷 103-107页

作者：谢恩江苏扬农化工集团有限公司江苏扬州225000

羰基是有机化学中重要的含氧官能团,许多有机化工原料含有羰基官能团(包括醛、酮、酸等)。C-C键和C-h键选择氧化断裂反应是生成羰基官能团的重要途径之一。本文以分子氧为氧化剂,以四氢糠醇为底物选择氧化制备γ-丁内酯(GBL),开发了催... 详细信息

羰基是有机化学中重要的含氧官能团,许多有机化工原料含有羰基官能团(包括醛、酮、酸等)。C-C键和C-h键选择氧化断裂反应是生成羰基官能团的重要途径之一。本文以分子氧为氧化剂,以四氢糠醇为底物选择氧化制备γ-丁内酯(GBL),开发了催化氧化制备羰基化合物的新体系。探讨了反应温度、反应压力、反应时间对催化活性的影响及催化剂循环使用的稳定性;在V/MCN催化剂作用下,四氢糠醇的转化率和GBL的选择性分别达到84.6%和92.8%;循环使用20次,催化剂活性未见明显降低。测试结果表明催化剂活性中心是分散的氧化钒物种,介孔氮化碳(MCN)材料作为一种碱性载体可以有效地抑制GBL的深度氧化。

关键词：介孔氮化碳钒氧化反应

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钢铁冶金废渣活化过硫酸盐降解丁基黄药

东北大学学报（自然科学版） 2024年第2期45卷 187-192页

作者：李美杭苗思雨张巍巍胡恩柱东北大学冶金学院辽宁沈阳110819 沈阳大学区域污染环境生态修复教育部重点实验室辽宁沈阳110044

以钢铁冶金废渣(钢渣、含钛高炉渣、提钒尾渣)活化过硫酸盐降解水中的丁基黄药.分析了废渣种类与用量、过硫酸盐浓度、初始ph等因素对丁基黄药降解效能的影响,采用双因素方差分析揭示了不同因素之间的交互特征.结果表明丁基黄药的降解... 详细信息

以钢铁冶金废渣(钢渣、含钛高炉渣、提钒尾渣)活化过硫酸盐降解水中的丁基黄药.分析了废渣种类与用量、过硫酸盐浓度、初始ph等因素对丁基黄药降解效能的影响,采用双因素方差分析揭示了不同因素之间的交互特征.结果表明丁基黄药的降解率随废渣用量和过硫酸盐浓度增加而增大.在废渣用量1 g/L,过硫酸盐浓度为0.5 mmol/L,反应时间96 h时,钢渣、含钛高炉渣、提钒尾渣活化过硫酸钠对丁基黄药的降解率分别可达96.47%,97.70%和95.12%.三种废渣活化效能分别在碱性、近中性和酸性条件下达到最优.其中钢渣活化以非自由基(^(1)O_(2))和SO_(4)·-,hO·共同作用;含钛高炉渣以^(1)O_(2)为主,伴随着hO·的产生;提钒尾渣则仅以^(1)O_(2)为主.

关键词：过硫酸盐丁基黄药钢渣含钛高炉渣提钒尾渣

Risk Factors for Cardiovascular Disease among hotel Workers, Bohicon, Benin

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Occupational Diseases and environmental Medicine 2024年第2期12卷 130-141页

作者： Mênonli Adjobimey Rose Mikponhoué Eméline Gbaguidi Esdras hountohotegbè hélène Sacca Paul Ayélo Vikkey Antoine hinson Unité de Recherche et d&#8217Enseignement en Sant&#233 au Travail et Environnement FSS Cotonou Cotonou Benin Service de Santé au Travail du Centre National Hospitalier Universitaire de Pneumo Phtisiologie de Cotonou Cotonou Benin Laboratoire d’ Epid&#233miologie des Maladies Chroniques et Neurologiques FSS Cotonou Benin

Introduction: Non-communicable diseases (NCDs) are on the increase in several sectors of activity. The aim of the study was to determine the frequencies of cardiovascular risk factors (CVRF) and factors associated with hypertension among hotel workers in the city of Bohicon. Methods: This was a descriptive and analytical cross-sectional study conducted in the period from December 2018 to January 2019. The variables studied were sociodemographic, occupational, anthropometric and behavioral. Participant recruitment was exhaustive. A standardized questionnaire inspired by the STEPS-WhO questionnaire was used for data collection. After the descriptive analysis, a bivariate analysis was performed using Pearson’s Chi-square test or Fisher’s test at the 5% threshold. Results: A total of 101 workers, 53 (52.47%) of them male, participated in the study. The mean age was 30.60 ± 8.20 years, with extremes of 18 and 55 years. The frequencies of the main risk factors were: 68.32% sitting position > 6 hours/day;38.61% shift work;21.78% high psychological demand, 82.18% low decision latitude, 24.75% low social support, 21.78% occupational stress;7 (6.93%) harmful alcohol consumption;6.93% tobacco consumption;48.51% insufficient physical activity;98.02% insufficient fruit and vegetable consumption;59.41% overweight;14.85% hTA. Factors associated with hypertension were: sex, age and marital status. Conclusion: Occupational factors need to be taken into account when assessing CVRFs. NCD control programs are needed in all sectors of activity. A larger study is needed in the hotel sector.

关键词： FDRCV Occupational Factors hypertension hotels Benin

内镜下注射去甲肾上腺素治疗脑梗死合并应激性消化道出血75例效果观察

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中国基层医药 2024年第1期31卷 40-44页

作者：汤静雯杨芮沈慧芸王恩丽水市人民医院重症监护室丽水323000 丽水市人民医院骨科丽水323000 浙江省台州医院神经外科台州318000

目的观察内镜下注射去甲肾上腺素治疗脑梗死合并应激性消化道出血临床效果。方法选择2020年10月至2021年10月丽水市人民医院重症监护室接收的脑梗死合并应激性消化道出血患者150例为研究对象,采用随机对照研究方法,按照随机数字表法分... 详细信息

目的观察内镜下注射去甲肾上腺素治疗脑梗死合并应激性消化道出血临床效果。方法选择2020年10月至2021年10月丽水市人民医院重症监护室接收的脑梗死合并应激性消化道出血患者150例为研究对象,采用随机对照研究方法,按照随机数字表法分为对照组(n=75)和观察组(n=75)。对照组给予常规临床治疗,观察组在此基础上予以内镜下注射去甲肾上腺素治疗。比较两组止血时间、输血量、住院时间,比较两组治疗前后的应激指标及炎症指标,评价两组止血效果及不良反应情况。结果观察组的止血时间、输血量、住院时间分别为(16.16±4.36)h、(385.35±41.28)mL、(5.35±1.28)d,均短于、少于对照组的(27.27±6.34)h、(447.07±32.07)mL、(7.07±2.07)d(t=12.50、10.22、6.12,均Ph)、超敏C反应蛋白(hs-CRP)、白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)水平分别为(288.33±19.53)mmol/L、(29.17±4.26)μg/L、(4.08±1.08)mU/L、(38.27±8.72)ng/L、(6.69±1.35)μg/L、(6.37±1.51)mg/L,均低于对照组的(327.22±22.01)mmol/L、(39.32±5.54)μg/L、(5.36±1.22)mU/L、(51.24±13.23)ng/L、(8.67±2.29)μg/L、(11.44±3.13)mg/L(t=11.44、12.57、6.80、7.08、6.45、12.63,均P0.05)。结论应用内镜下注射去甲肾上腺素治疗脑梗死合并应激性消化道出血,可快速止血,且可有效改善患者的炎症及应激指标,安全性高。

关键词：脑梗死消化性溃疡出血止血,内窥镜去甲肾上腺素四氢皮质醇 C反应蛋白质白细胞介素6 肿瘤坏死因子α