Experimental study ofcasing wear under impact-sliding conditions

Theoretical analysis and field monitoring show that lateral vibration has very important effect on casing wear in deep & ultra-deep well drilling. The wear mechanism of casing under impact-sliding work conditions has been investigated and many experiments have been completed with a newly developed full-scale casing wear test machine. Test results present that adhesion wear, contact fatigue, and grinding abrasion are the main wear mechanisms under impact-sliding test conditions. The friction coefficient and linear wear rate of the casing rise obviously with an increase in impact load. And the larger the impact load, the rougher the worn surface of the casing. The linear wear rate decreased slightly but the average friction coefficient increased slightly with an increase in impact frequency under an impact load of 2,500 N. Both the linear wear rate of the casing and the average friction coefficient increased substantially with an increase in impact frequency under an impact load of 4,000 N. Under lower impact load conditions, grinding abrasion and contact fatigue are the main mechanisms of casing wear; under higher impact load conditions, adhesion wear and contact fatigue are the main mechanisms of casing wear.

Surface Geophysical Methods used to Verify the Karst Geological Structure in the Built-up Area:A Case Study of Specific Engineering-Geological Conditions

This article presents a research study of complex limestone karst engineering-geological conditions in the municipality Valaskanear Banska Bystrica in Slovakia.The aim of the study is to demonstrate the impossibility of spatial identification of cave spaces using surface geophysical methods due to the specific engineering-geological conditions of a thick surface layer of anthropogenic fill containing highly heterogeneous anthropogenic material.Its maximum thickness is 3 m.Another specificific condition of the study area is its location in the built-up area,due to which the applicability of geophysical methods was limited.The article contains methodological recommendations to be used in analogous geological conditions with karst structures topped with anthropogenic fill,which complicates the identification of cave spaces.The recommended solution herein is the identification of the cave system using underground mapping of the karst and its projection onto the surface for which surface geophysical methods have been combined.

A Study on Palaeogeography and Metallogenic Conditions of Early Carboniferous Bauxite Deposits of Old Weathered Crust in Guizhou, Sichuan, Hunan and Hubei Provinces

There are four subtypes. namely, Ia, Ib, Ic and Id of the Early Carboniferous bauxite deposits of the old weathered crust type in Guizhou, Sichuan, Hunan and Hubei provinces. They are all distributed in the Upper Yangtze old land. As a result of the Hunan-Guizhou palaeo-faulting, the crust on the northern side of the fault was uplifted and became land, thus suffering denudation. The bauxitic substances left in the weathered crust evolved and were reworked into bauxite. On the other hand, the crust on the southern side of the fault sank and remained to be part of an ocean. The bauxite deposits of Ia and Ib subtypes were formed by in-situ enrichment of residual bauxitic substances in the weathered crust of the old land, but bauxite deposits of Ic and Id subtypes resulted from transportation, accumulation and sedimentation of allothogenous bauxitic substances on the weathered crust of the old land. The processes of transportation may be distinguished as dry transportation and wet transportation, both of which proceeded under atmospheric conditions.

MARINE SOURCE ROCKS AND THEIR DEPOSITIONAL CONDITIONS OF MESOZOIC—CENOZOIC IN THE GAMBA—TINGRE BASIN,SOUTH TIBET:ORGANIC GEOCHEMICAL STUDY

The Gamba—Tingri basin lies in south Tethys Himalaya subzone. It is 400km in length from east to west, and 30～50km in width from north to south. The basin is mainly made up of marine Mesozoic and Lower Cenozoic, i.e., Jurassic, Cretaceous, and Lower Tertiary. Its total strata are more than 3100m in thickness. The passive continental margin of the India plate developed during Jurassic—Cretaceous after a Triassic rifting stage. Collision took place between the India and the Eurasian plate during the latest Cretaceous and earliest Tertiary (Liu and Einsele, 1994), which resulted in a Tertiary residual basin.The Jurassic stratigraphic system in the Gamba—Tingri basin were not carried out until recently (Wan et al., 1999), which is divided into three formations, i.e.., Pupuga Fm., Nieniexiongla Fm., and Menkadun Fm.. The Cretaceous and Tertiary stratigraphic system is after Wan (1985) and Xu et al.(1990), which the Cretaceous is divided into six formations: Dongsan Fm., Chaqiela Fm., Lengqingle Fm., Xiawuchubo Fm., Jiubao Fm., and Zongshan Fm, whereas the Tertiary is divided into Jiabula Fm. Zongpu Fm., and Zhepure Fm.

STUDY ON THE ADDITION REACTION OF 1-IODO-4-CHLOROPERFLOROBUTANE TO 1-HEXENE UNDER REDUCTIVE CONDITIONS

Promoted by various reductants,the addition of 1-iodo-4-chloro- perfluorobutane to 1-hexene giving 1:1 adduct is reported.Based on these facts,several new redox systems are proposed.

THE APPLICATION OF MICROELECTRODE TO THE STUDY OF MULTISTEP ELECTRODE PROCESSES UNDER STEADY STATE CONDITIONS PART I EE MECHANISM

Under steady-state conditions, the general currents of EE reactions at disk,hemispherical and spherical microelectrodes are derived.From these equations, some electrode reaction parameters can be very simply obtained.

Study on Conditions for Enhancing Innovation Capacity of China's Textile Industry

The formation and maintenance of the innovation capacity of our textile industry does not only have to do with the sustainable development of textile industry itself,but also directly decides the international competition

Risk Factors for Birth Defects: A Conditional LogisticRegression Analysis of a Case-Control Study in Guang-dong Province of China

Information was obtained from the same questionnaire (23 risk factors listed) of cases and controls. We used a multivariate logistic model, which described variables significantly increased risk of birth defects. The risk factors included maternal educational levels, medicine taken during pregnancy and antenatal care. It was suggested to strengthen antenatal care was the main preventive measure against birth defects.

An On-line Ferrograph for Monitoring Machine Wear

In order to improve an on-line ferrograph, this paper simulates a three-dimensional magnetic field distribution of an electromagnet, builds a sinking motion model of a wear particle, and investigates the motion law of wear particles under two different conditions. Both numeric results and experimental results show that the on-line ferrograph is capable of monitoring machine wear conditions by measuring the concentration and size distribution of wear particles in lubricating oil.

Therapeutic Approach for Hair Growth and Regeneration Using Bioactive Formulation Containing Mesenchymal Stromal Cell-Derived Conditioned Medium

Background and Aims: Androgenetic alopecia (AGA) is a common form of hair loss in both men and women. Despite its high prevalence and associated patient morbidity, the approved therapeutic options are limited to finasteride and minoxidil. The present study is aimed at assessing the efficacy of hair serum formulation, Trichosera®containing Bone marrow-derived mesenchymal stromal cells conditioned media as an active ingredient, for hair fall control and hair regrowth in healthy Indian human volunteers. Methods: The product was made using a 20% concentration of 10X Conditioned Media along with excipients. The final product was tested for physicochemical parameters, biomarkers, total protein content and microbial limits as per our in-house specifications. Results: The primary irritation patch test showed that the product is non-irritant and dermatologically safe. A clinical study on 40 subjects was conducted to evaluate the effectiveness of the bioactive formulation in hair fall control and hair regrowth in healthy volunteers. Phototrichogram measurement showed hair density and hair growth rate increased significantly by 11.54% and 18.66% at week 24. Hair tensile strength also increased significantly by 41.10% at 12 weeks follow-up. Hair pull test, to see a reduction in pulled hair and comb’s test to show a decrease in hair fall significantly improved from week 4 onwards. There were no significant adverse events in response to the product application. Conclusion: It is concluded that the hair serum product is completely safe on direct application to the scalp and showed significant improvement in the hair growth rate, hair density, scalp condition and reduction in hair fall. .

基于文献计量分析皮内针疗法适宜病症与临床应用进展

目的基于文献计量分析皮内针疗法的临床文献,探讨皮内针疗法的适宜病症与临床应用进展。方法通过计算机检索中国知网(CNKI)、万方数据库(Wanfang data)和维普中文期刊数据库中与皮内针疗法相关的临床研究文献,应用文献计量学的方法对皮内针疗法发文量、病谱和适宜病症进行分析。结果临床涉及论文共2220篇,近10年发文量显著增长。皮内针疗法临床涉及病症208种。一级适宜病症为手术后疼痛、失眠症、偏瘫、面神经麻痹;二级适宜病症为肩痛、颈椎病、癌痛、膝骨关节炎、腰椎间盘移位、便秘、头痛;三级适宜病症为带状疱疹、遗尿、放化疗后不良反应、变应性鼻炎、呃逆、面肌痉挛;四级适宜病症包括痛经、高血压、糖尿病、胃肠功能紊乱、痹证、吞咽障碍、腰扭伤、肥胖症。结论皮内针疗法是近年来的临床研究热点,其治疗疾病以痛症居多,其次为各类慢性病。不同针具中,揿针的应用受到广泛关注。

社区共病老年人居家疾病体验的质性研究

背景面对老年慢性病患病率高、多种慢性病共存形势带来的严峻挑战,社区共病老年人的健康问题亟待关注。共病管理模式正不断被探索实践,疾病体验作为来自患者自我报告的健康信息有望成为“以患者为中心”社区共病管理模式的重点内容。目的 深入了解社区共病老年人居家的真实疾病体验,为社区共病老年人的个性化健康管理和支持策略提供依据。方法 采用目的抽样法、最大差异化抽样于2022年8—9月在郑州市某社区卫生服务中心所管辖的4个社区中抽取符合条件的访谈对象,基于信息饱和的原则最终纳入20例研究对象。在研究目的、文献回顾及专家咨询结果的基础上初步拟定访谈提纲,预访谈2例后确定最终访谈提纲。以现象学研究方法为指导,对研究对象进行半结构式访谈。采用Golaizzi分析法分析资料。结果 共提炼出4个主题和11个亚主题,主要有长期存在的症状困扰(身体功能障碍、疲劳、睡眠障碍、疼痛)、负性心理体验(对未来生活的无助感和担忧、社会价值感和自我认同感降低、社交活动改变的孤独感)、与共病和谐共存的积极心态(感恩知足、积极适应)、困境下的期望(希望功能改善、寻求多方社会支持)。结论 身体功能障碍、睡眠障碍、疲劳、疼痛是社区共病老年人最关注的健康困扰,社区共病老年人的症状管理和多元社会支持有待加强。未来有望采用多维数据进行动态化健康评估,探索共病的共性和个体性规律,实现社区共病的精准管理及干预。

东京奥运会国家步枪射击运动员体能训练实证研究

目的:对东京奥运会我国步枪射击运动员基础体能和专项体能数据进行系统梳理和深度挖掘,总结和提炼体能训练备战策略,以期为我国高水平步枪射击运动员体能训练向着专业化、精细化和精准化方向高质量发展提供参考。方法:通过专家访谈和问卷调查形成步枪射击运动员专项体能测试指标;对运动员10项基础体能指标和4项专项体能指标进行测试,并根据前测结果制订16周集训计划;通过独立样本T检验和配对样本T检验对训练效果进行组间和组内差异性检验;采用曲线回归探索基础体能和专项成绩间的关系。结果:1)东京奥运会入选队员和未入选队员基础体能整体无显著性差异;2)东京奥运会获奖运动员各项基础体能测试数据互有高低,呈现出明显的个性化特征;3)步枪射击运动员基础体能(X)和专项成绩(Y)之间呈倒U形关系,二次曲线回归方程Y=0.331+-0.14*X+-0.038*X2,校正R2=0.27;4)集训后组内比较发现男女子运动员各专项体能测试指标均非常显著性的高于训练前。结论:1)步枪射击运动员基础体能与专项成绩或呈“倒U形”关系;2)步枪射击运动员专项体能水平满足项目特征需求后,专项体能水平的高低不再是影响其专项成绩的关键因素,而不同专项体能间发展的均衡程度或成为影响专项成绩的关键因素;3)步枪射击运动员专项体能训练策略应重点考虑核心力量耐力、下肢力量耐力、有氧能力和平衡能力4个方面。

蓄/取热工况套管式地埋管换热器换热特性试验研究

为研究竖直套管式地埋管的非稳态传热特性,通过搭建竖直套管式地埋管传热特性砂箱试验台,对竖直套管式地埋管进行了试验研究,分析了蓄热工况和取热工况下不同运行模式对竖直套管式地埋管以及其周围土壤传热特性的影响,获得了竖直套管式地埋管流体的进出口水温、周围土壤温度、单位井深换热量以及平均传热系数的变化规律。试验研究结果表明:蓄热工况下在间歇运行模式分别为1∶1与1∶2情况下,启停比越小,地埋管周围土壤温度波动范围越大;取热工况下,距离地埋管径向距离越远的土壤温度受启停比时间的影响较小;间歇运行模式下的单位井深换热量比连续运行模式下单位井深换热量高,运行72 h时启停比1∶1模式下单位井深换热量比连续模式下单位井深换热量高157.98 W/m。可见间歇运行模式有利于土壤恢复,实际工程中可根据建筑要求合理选择间歇运行。

太原市老年人膳食行为现状及其影响因素

目的:调查分析太原市老年人膳食行为现状及其影响因素,并了解老年人健康状况。方法:2023年5月—8月选取太原市多个社区的650名老年人为研究对象,使用老年人社会人口学资料调查表、老年人膳食行为习惯调查量表、简明健康调查表(SF-36)进行调查分析。结果:650名老年人中,膳食行为优62人、良510人、中78人。不同文化程度、月收入、既往职业、婚姻状况、是否患有慢性病的老年人膳食行为水平不同(P<0.05)。650名老年人生理功能得分为(83.56±11.54)分,情感职能得分为(82.45±6.98)分,生理职能得分为(77.78±7.98)分,躯体疼痛得分为(68.97±4.21)分,生命活力得分为(75.41±6.28)分,社会功能得分为(78.44±8.68)分,精神健康得分为(74.13±10.34)分,总体健康得分为(59.85±16.52)分。结论:太原市老年人膳食行为受文化程度、月收入、既往职业、婚姻状况、是否患有慢性病影响,健康状况有待提升,需要及时采取行之有效的干预措施,提升老年人的健康水平,使其保持健康的生活与膳食习惯。

In-situ study of the hydrogen peroxide photoproduction in seawater on carbon dot-based metal-free catalyst under operation condition

Hydrogen peroxide(H_(2)O_(2))photoproduction in seawater with metal-free photocatalysts derived from biomass materials is a green,sustainable,and ultra environmentally friendly way.However,most photocatalysts are always corroded or poisoned in seawater,resulting in a significantly reduced catalytic performance.Here,we report the metal-free photocatalysts(RUT-1 to RUT-5)with in-situ generated carbon dots(CDs)from biomass materials(Rutin)by a simple microwave-assisted pyrolysis method.Under visible light(λ≥420 nm,81.6 mW/cm^(2)),the optimized catalyst of RUT-4 is stable and can achieve a high H_(2)O_(2)yield of 330.36μmol/L in seawater,1.78 times higher than that in normal water.New transient potential scanning(TPS)tests are developed and operated to in-situ study the H_(2)O_(2)photoproduction of RUT-4 under operation condition.RUT-4 has strong oxygen(O_(2))absorption capacity,and the O_(2)reduction rate in seawater is higher than that in water.Metal cations in seawater further promote the photo-charge separation and facilitate the photo-reduction reaction.For RUT-4,the conduction band level under operating conditions only satisfies the requirement of O_(2)reduction but not for hydrogen(H2)evolution.This work provides new insights for the in-situ study of photocatalyst under operation condition,and gives a green and sustainable path for the H_(2)O_(2)photoproduction with metal-free catalysts in seawater.

社区非酒精性脂肪肝病人群常见慢性病共病组合及变化情况分析

目的:了解社区非酒精性脂肪肝病人群常见慢性病共病组合及变化情况,为社区人群的慢性病共病防治提供科学依据。方法:基于上海市自然人群队列松江子队列,针对社区人群于2016年和2019分别开展基线调查与随访,采用问卷调查收集人群常见慢性病患病情况,比较随访前后非酒精性脂肪肝病患者共患其他慢性病的变化情况,中位随访时间为2.96年。结果:随访前后比较,社区人群非酒精性脂肪肝病总体患病率由38.68%增长至40.78%,单纯患非酒精性脂肪肝病人群占比由34.60%提高至37.92%,共患病以高血压、糖尿病、高脂血症、甲状腺疾病、慢性胃肠炎最为常见,随访阶段发现共患高血压和糖尿病的人群占比进一步升高。结论:社区人群非酒精性脂肪肝病患病率较高,共患高血压、糖尿病、高脂血症最为常见。因此,社区非酒精性脂肪肝病人群共患其他慢性病的调查结果和慢性病管理应引起社区医疗卫生机构的重视,从而促进社区人群的健康水平。

利用条件错误发现率方法识别抑郁症和失眠症的多效性位点

背景 抑郁症和失眠症常共病存在,两者存在一些共同的发病机制,并可能受相同的多效性基因调控。既往全基因组关联研究(GWAS)一般采用单性状研究,在解释基因多效性方面存在一定的狭窄性。目的 识别与失眠症和抑郁症相关的遗传变异位点,检验抑郁症和失眠症是否存在共同的遗传因素。方法 抑郁症GWAS数据来自精神疾病遗传学联盟(PGC),共包含246 363例抑郁症患者和561 190例正常对照。失眠症GWAS数据来自睡眠障碍知识门户,共包含1 331 010例受试者。采用条件错误发现率(cFDR)和联合的条件错误发现率(ccFDR)方法筛选与抑郁症和失眠症相关的遗传位点,采用通路富集分析检验这些位点的生物学功能。结果 抑郁症和失眠症存在显著的多效性富集现象。利用cFDR方法,以cFDR<0.01作为显著性阈值,鉴定出21个易感位点与抑郁症相关(其中17个是新识别的),38个易感位点与失眠症相关(其中28个是新识别的)。以ccFDR<0.05为显著性阈值,识别出16个多效性位点与抑郁症和失眠症均相关,其中15个是本研究新识别的。通路富集分析结果显示,与抑郁症和失眠症均关联的易感位点富集于突触传递相关通路,如突触后密度(GO:0014069,P=4.91E-04,FDR=4.84E-03)、不对称突触(GO:0032279,P=5.09E-0,FDR=4.84E-03)、突触后膜神经递质受体水平的调节(GO:0099072,P=5.11E-04,FDR=1.69E-02)。结论 失眠症与抑郁症之间存在多效性富集现象,其共病机制与突触传递有关。

降雨下桥墩堆积体稳定性自动化监测研究及应用

为研究降雨条件下广汕高速铁路(广州—汕尾)斧头石特大桥富水堆积体地层及桥墩的稳定性问题,开展一体自动化监测技术研究,分析施工及施工后18个月内土体变形沉降、孔隙水压力、降雨量、地表水位的变化,探讨降雨下堆积体地层及桥墩的位移规律。结果表明:桥墩对边坡上部堆积体地层位移起到了抑制作用,其左侧地层产生挤压,局部地表隆起后趋于稳定;监测段在第6—第11月内存在间歇性强降雨天气,改变了堆积体地层的蠕动变形模式,影响了地层对桥桩的侧向作用力,桥桩左侧承台因此发生偏移,但在顶部桥梁和底部稳定性地层的约束作用下恢复至稳定状态;在监测期内工程现场未发生堆积体边坡及桥墩失稳现象,综合地表沉降、深层位移、桥墩沉降数据分析,地层和桥梁均处于稳定状态。