Effect of Ellipsoidal Particle Shape on Tribological Properties of Lubricants Containing Nanoparticles

Adding nanoparticles can significantly improve the tribological properties of lubricants.However,there is a lack of understanding regarding the influence of nanoparticle shape on lubrication performance.In this work,the influence of diamond nanoparticles(DNPs)on the tribological properties of lubricants is investigated through friction experiments.Additionally,the friction characteristics of lubricants regarding ellipsoidal particle shape are investigated using molecular dynamics(MD)simulations.The results show that DNPs can drastically lower the lubricant's friction coefficientμfrom 0.21 to 0.117.The shearing process reveals that as the aspect ratio(α)of the nanoparticles approaches 1.0,the friction performance improves,and wear on the wall diminishes.At the same time,the shape of the nanoparticles tends to be spherical.When 0.85≤α≤1.0,rolling is ellipsoidal particles'main form of motion,and the friction force changes according to a periodic sinusoidal law.In the range of 0.80≤α<0.85,ellipsoidal particles primarily exhibit sliding as the dominant movement mode.Asαdecreases within this range,the friction force progressively increases.The friction coefficientμcalculated through MD simulation is 0.128,which is consistent with the experimental data.

玻璃钢与碳纤维头罩应用对比分析

以城轨车辆头罩为研究对象,对比分析了玻璃钢和碳纤维头罩在结构设计、力学性能及与车体连接结构的差异性。头罩与车体的连接方式可采用“粘接”或“粘接+机械连接”的方式。从轻量化角度考虑,碳纤维头罩相比玻璃钢头罩更轻,在未来轨道交通装备的轻量化发展中具有更好的应用前景,在力学性能方面碳纤维头罩要优于玻璃钢头罩,但在隔声降噪方面玻璃钢头罩性能更优,且碳纤维头罩对电磁波信号有着明显的减弱作用,不利于车辆天线信号的接收。结合仿真计算分析和冲击试验检测结果表明玻璃钢和碳纤维材质的头罩均可以满足其使用性能要求。

Research on the Reform of Practical Teaching of Internet of Things Engineering in the Context of New Engineering

The emergence of new engineering disciplines has resulted in the growing trend of cross-discipline,and the enhancement of students’technical application ability has become the main teaching objective of engineering disciplines.For this reason,the Internet of Things(IoT)engineering program should be actively reformed,providing students with sufficient opportunities to improve their practical skills.This paper identifies the challenges within practical teaching of IoT engineering,delves into effective strategies for practical IoT teaching within the context of emerging engineering disciplines,and presents practical teaching experiences from the School of Information Engineering at Hainan University of Science and Technology as a case study.The aim is to offer guidance and insights to educators in this field.

Corrosion Prevention of the Generator Stator Hollow Copper Conductor and Water Quality Adjustment of Its Internal Cooling Water

On the basis of expounding the corrosion mechanism of the stator hollow copper conductor in the water-cooling generator, methods of preventing corrosion of the stator hollow copper conductor in the wa-ter-cooling generator through adjusting water quality of its cooling water have been proposed. For internal water cooling systems which are airtight, the corrosion of the hollow copper conductor can be prevented through keeping foreign oxygen and carbon dioxide from entering the system, and the amount of oxygen in the internal water can be lowered by blowing high purity nitrogen. For systems not airtight, the corrosion of the hollow copper conductor can be inhibited through lowering the amount of oxygen to some extent by sealing and increasing pH value by processing part of cooling water with bypass small flow sodium-type mix-bed.

支气管镜下肺泡灌洗液半乳甘露聚糖试验联合（1,3）-β-D葡聚糖检测对肺曲霉菌病的诊断价值

目的探讨支气管镜下肺泡灌洗液(BALF)半乳甘露聚糖(GM)试验联合(1,3)-β-D葡聚糖检测(G试验)对肺曲霉菌病的诊断价值。方法选取2013年5月-2016年12月在该院住院的30例确诊为肺曲霉菌病的患者作为研究对象,定为研究组,30例非真菌感染患者为对照组,所有患者均支气管镜下采集BALF,并同时采集血清标本进行GM试验和G试验,比较单独和联合试验的检测结果。结果研究组中,BALF GM试验阳性21例,G试验阳性25例;血清GM试验阳性19例,G试验阳性23例;BALF GM联合G试验阳性27例;血清GM联合G试验阳性26例。BALF GM试验联合G试验检测灵敏度、特异性、阳性预测值、阴性预测值和准确度分别为90.0%、93.3%、93.1%、93.3%和91.0%。结论支气管镜下BALF GM试验联合G试验检测对肺曲霉菌病的诊断临床价值高,可作为诊断肺曲霉菌病的重要辅助诊断手段。

不同浓度聚维酮碘二次冲洗法对白内障手术结膜囊消毒效果的评价

目的:评价不同浓度聚维酮碘二次冲洗法对白内障手术结膜囊消毒的效果。方法:选取我院眼科2016-08/2017-10接受白内障超声乳化联合人工晶状体植入术治疗的白内障患者600例600眼,术前、开睑后两次采用聚维酮碘冲洗法对结膜囊消毒,根据聚维酮碘二次冲洗所使用浓度不同将患者分为Ⅰ组320例、Ⅱ组280例,浓度分别为0.025%、0.05%。两组一次、二次冲洗后获取结膜囊拭子标本进行细菌鉴定,二次冲洗时评定患者的主观舒适度及球结膜充血、角膜上皮损伤情况,并统计术后眼内炎发生情况。结果:Ⅰ组、Ⅱ组聚维酮碘一次、二次冲洗后细菌培养阳性率比较均无差异(P>0.05)。Ⅰ组结膜囊二次冲洗时异物感、痒感、畏光、眼红等主观感觉发生率明显低于Ⅱ组(P<0.05)。Ⅰ组结膜囊二次冲洗后球结膜充血、角膜上皮损伤程度较Ⅱ组显著低(P<0.05)。Ⅰ组、Ⅱ组术后分别有2眼(0.6%)、1眼(0.4%)发生眼内炎(P>0.05)。结论:0.025%聚维酮碘已有高效的消毒作用,与0.05%聚维酮碘相比,其对于改善患者主观舒适度及减轻球结膜充血、角膜上皮损伤更有优势,更适用于白内障手术患者。

银杏叶提取物治疗肺纤维化的作用机制

肺纤维化是一种原因不明的慢性间质性肺疾病,目前尚无安全有效的治疗方法。银杏叶提取物(GBE)是从银杏叶中提取的一种化合物,其能对抗大鼠肺纤维化,且安全性高。该文对GBE抗肺纤维化的作用机制的研究进展,具体有改善氧化应激、抑制细胞凋亡、调控细胞因子网络(转化生长因子β1、肿瘤坏死因子-α、结缔组织生长因子等)及基质金属蛋白酶-9/金属蛋白酶组织抑制剂-1系统平衡进行综述。

ZrO_2晶型对铜基粉末冶金摩擦材料摩擦学性能的影响

采用粉末冶金加压烧结技术制备含单斜和立方2种晶型ZrO_2的铜基摩擦材料,研究在干摩擦及不同制动速度条件下,ZrO_2晶型对铜基粉末冶金摩擦材料摩擦学性能的影响;用光学表面分析仪和扫描电子显微镜分别对试样磨损表面形貌及磨屑形貌进行观察,探究ZrO_2晶型对粉末冶金摩擦材料摩擦学性能的作用机制。结果表明:在相同条件下,含单斜相ZrO_2摩擦材料的摩擦因数及磨损量均高于含立方相ZrO_2的摩擦材料;随着制动速度的升高,2种材料的摩擦因数均降低,而含立方相ZrO_2材料摩擦因数降幅较小,同时两者的磨损量均呈现先上升后降低的趋势。随制动速度提升,含单斜相ZrO_2的摩擦材料主要磨损机制由黏着磨损与犁削磨损转变为剥层磨损;而含立方相ZrO_2的摩擦材料主要磨损机制由犁削磨损转变为犁削磨损与氧化磨损,最后转变为剥层磨损。

涡轮增压器用无铅止推轴承材料摩擦学性能研究

针对涡轮增压器用止推轴承材料的无铅化,采用粉末冶金工艺分别制备Cu Sn6.5P0.1无铅和Cu Sn10Pb10含铅止推轴承材料,并对比研究2种材料的微观组织结构及油润滑和乏油条件下材料的摩擦学性能。结果表明:微观组织结构上,Cu Sn6.5P0.1区别于Cu Sn10Pb10的硬基体(Cu合金基体)+软相(Pb)"两相"组织,呈"单相"组织;Cu Sn6.5P0.1的力学性能要优于Cu Sn10Pb10;在油润滑条件下,Cu Sn6.5P0.1和Cu Sn10Pb10的摩擦学性能基本一致,在乏油润滑条件下,Cu Sn6.5P0.1的摩擦因数更加平稳;乏油润滑条件下Cu Sn10Pb10形成了富Pb和Fe的润滑膜使摩擦因数保持平稳,Cu Sn6.5P0.1则形成Fe氧化物膜保证材料稳定的摩擦因数。Cu Sn6.5P0.1材料各项性能相当或优于Cu Sn10Pb10,满足涡轮增压器用止推轴承材料的无铅化要求。

结膜吸吮线虫感染幼童2例及其流行现状分析

本文报告2例四川地区幼童感染结膜吸吮线虫,并对结膜吸吮线虫的感染现状进行文献分析。采集2017和2021年四川地区发现的2例患者的病史资料,对从患者眼内取出的虫体行肉眼和低倍显微镜下形态学观察,根据虫体形态和临床症状,诊断为结膜吮吸线虫病。2017-2021年,我国文献报道结膜吸吮线虫病12例,其中男性8例,女性4例,分布在9个省和直辖市;年龄最小11个月,最大83岁;多来自农村,儿童居多;发生于夏秋季,症状视感染程度轻重而不同。结膜吮吸线虫病可通过患者病史、症状和虫体形态学诊断,作为人畜共患病,近5年持续散在出现,成年患者以农村居民居多,幼童则农村和城市都有,且此次2例均来自中小城市,建议针对性加强户外环境治理和家庭卫生习惯的宣传,进一步健全流浪动物的收养措施和宠物的卫生管理。

包虫病特异性抗体检测试剂盒诊断效能评价及结果判定优化

为评价3种包虫病特异性IgG抗体诊断试剂盒的临床诊断效能,并针对其特异度差的问题进行优化,为包虫病免疫学诊断提供检测结果优化判定的策略,本研究共收集87例包虫病确诊病人血清,78例经排查为非包虫病就诊病人血清。每份血清同时采用3种试剂盒进行检测,对结果进行统计分析,评价各方法的诊断效能。通过受试者工作特征(ROC)曲线寻找各方法最佳诊断界值。采用胶体金免疫渗滤斑点法(DIGFA)对酶联免疫吸附法(ELISA)或胶体金免疫层析法(GICA)所得检测结果低于最佳诊断界值的阳性样本进行重新测定,以DIGFA法最佳诊断界值为结果判定标准。比较结果优化前后的诊断效能。结果显示,3种诊断方法的灵敏度在90.8%~94.3%之间,特异度在75.7%~83.3%之间。ROC曲线所得最佳诊断界值均高于试剂盒的cutoff值。检测结果经优化后,灵敏度保持在90.3%以上,特异度提升至88.5%以上。结果表明,3种诊断方法的特异度均不理想,本次研究通过对检测结果的优化判定,在不影响灵敏度的前提下可减少该部分血清假阳性结果的误判,提高方法的特异度,为包虫病临床诊断提供更为可靠的信息。

成都市曼氏裂头蚴病1例

本文报道1例曼氏裂头蚴人体寄生病例。通过肉眼和低倍显微镜下观察,根据虫体形态并结合临床,虫体鉴定为曼氏裂头蚴。裂头蚴的感染在城市中也存在潜在危险,应重视城市卫生防御,加强对城市小区卫生环境系统性管理。

一级学科统整视角下的有机化学课程群建设及教学改革

基于一流课程建设理念、以一级学科统整为指导,以有机化学课程为例讨论了如何加强二级学科课程间的协作以及如何基于“问题解决”(PBL)教学模式进行教学的问题。

Phase Ⅱ open-label study of recombinant circularly permuted TRAIL as a single-agent treatment for relapsed or refractory multiple myeloma

Background: Despite the recent development of new therapies, multiple myeloma(MM) remains an incurable disease. Thus, new, efective treatments are urgently needed, particularly for relapsed or refractory MM(RRMM). In an earlier phase I study, a novel form of recombinant human Apo2L/tumor necrosis factor-related apoptosis-inducing ligand(TRAIL) that is currently in clinical development for the treatment of hematologic malignancies, i.e., circularly permuted TRAIL(CPT), was well tolerated at a dose of 2.5 mg/kg per day and showed promising preliminary activity in patients with RRMM. This phase II, open-label, multicenter study further investigated the eicacy and safety of 2.5-mg/kg per day CPT as single-agent therapy for patients with RRMM.Methods: Patients with RRMM were treated once daily with CPT(2.5 mg/kg, intravenously) for 14 consecutive days for each 21-day cycle. Clinical response and toxicity were assessed after each treatment cycle.Results: Twenty-seven patients received CPT. Using the European Group for Blood and Marrow Transplantation criteria, we calculated the overall response rate of 33.3% with 1 near-complete response(n CR) and 8 partial responses(PRs). The clinical beneit rate(48.1%) included 1 nCR, 8 PRs, and 4 minimal responses. The most common treatmentrelated adverse events(TRAEs) were fever, aspartate aminotransferase elevation, alanine aminotransferase elevation, leucopenia, rash, neutropenia, and thrombocytopenia. We graded toxicity using the Common Toxicity Criteria for Adverse Events, version 3.0, and determined that 37.0% of patients had at least 1 grade 3–4 TRAE.Conclusions: CPT as a single agent can elicit a response in patients with RRMM and is well tolerated. Further clinical investigation is warranted.

Detection and Prevention of Environmental Hormone

The sorts and detection methods of environmental hormone were analyzed firstly,and then the effects of environmental hormone on organisms and humanity were discussed. Finally the control measures of environmental hormone pollution,such as reducing the use of goods and pesticide and the study of new substitutes and degradation technology are advanced.

Packed red blood cell transfusions as a risk factor for parenteral nutrition associated liver disease in premature infants

AIM To determine if packed red blood cell transfusions contribute to the development of parenteral nutrition associated liver disease. METHODS A retrospective chart review of 49 premature infants on parenteral nutrition for > 30 d who received packed red blood cell(PRBC) transfusions was performed. Parenteral nutrition associated liver disease was primarily defined by direct bilirubin(db) > 2.0 mg/dL. A high transfusion cohort was defined as receiving > 75 mL packed red blood cells(the median value). KaplanMeier plots estimated the median volume of packedred blood cells received in order to develop parenteral nutrition associated liver disease.RESULTS Parenteral nutritional associated liver disease(PNALD) was noted in 21(43%) infants based on db. Among the 27 high transfusion infants, PNALD was present in 17(64%) based on elevated direct bilirubin which was significantly greater than the low transfusion recipients. About 50% of the infants, who were transfused 101-125 mL packed red blood cells, developed PNALD based on elevation of direct bilirubin. All infants who were transfused more than 200 mL of packed red blood cells developed PNALD. Similar results were seen when using elevation of aspartate transaminase or alanine transaminase to define PNALD.CONCLUSION In this retrospective, pilot study there was a statistically significant correlation between the volume of PRBC transfusions received by premature infants and the development of PNALD.

某中心参加2016—2020年全国生物剂量估算能力考核结果的分析

采用回顾性调查方法,收集本实验室2016—2020年参加全国生物剂量估算能力考核结果的资料,分析影响生物剂量估算能力考核的因素。结果表明,10个考核样本中,8个样本剂量估算值相对偏差≤20%,2个样本剂量估算值相对偏差>20%。结果显示,实验室系统误差和人员能力是影响考核结果的主要因素,建立剂量-效应曲线,加强技术人员染色体dic+r分析能力,是减少系统误差和提升实验室考核能力的关键。

Effects of surface nanostructure on boundary lubrication using molecular dynamics

Molecular dynamics simulations are used to study the boundary lubrication behaviors of squalane lubricant between two iron wall structures during shearing at different pressures and temperatures.Boundary lubrication models with a smooth iron wall and a nanostructured iron wall,respectively,are constructed,and the density distribution of the lubricating film and the velocity distribution in the shearing process are analyzed.The mechanical response of the solid wall is output,and the friction coefficient is calculated.A tribological test is performed with a UMT-2 tribometer under sliding conditions to evaluate the reliability of the simulation method.The results show that the surface nanostructure has a significant effect on the film thickness and delamination of the lubricating film but little effect on the velocity distribution of the lubricating film.The nano strip groove helps to reduce the friction coefficient of the boundary lubrication system.

Extraction Hydrolysates from Larimichthys Polyactis Swim Bladder Using Enzymatic Hydrolysis

As a kind of biopolymer,hydrolysates of fish swim bladder,safer than those of land mammals,are widely used in food,cosmetics as well as pharmaceutical and biomedical fields for their biocompatibility,biodegradability,and weak antigenicity.To enhance hydrolysate production,in this paper,the papain and alcalase hydrolysis processes of larimichthys polyactis swim bladder were optimized with orthogonal experiments.With 89.5%hydrolysate yield,the optimal processing conditions for alcalase were solid-liquid ratio of 1:30,enzyme concentration of 0.7%,and extraction time of 6 h.As for papain,under the optimal processing conditions:solid-liquid ratio of 1:20,enzyme concentration of 0.5%,and extraction time of 8 h,the hydrolysate yield was 65.1%.To obtain higher hydrolysate yields,the ultrasonic pretreatments were implemented before the optimal enzyme hydrolysis processes.With ultrasonic waves of 100 W for 50 min,the hydrolysate yields were increased 2.1%(alcalase)and 4.5%(papain),respectively.The Fourier Transform Infrared(FTIR)spectroscopic analysis revealed that the hydrolysates extracted by papain exist in triple-helical forms.The Ultra-Violet(UV)absorption spectra indicated that the aromatic amino acids in the hydrolysates had strong absorptions in the wavelength range of 240 nm–300 nm.The results of this research demonstrate that the alcalase hydrolysates have better solubility in water and the solution is more stable under ambient temperature.However,the hydrolysates extracted by papain have a gel property and are insoluble in weak acid at room temperature,which is more suitable for applications in feedstock of biomedical.

2020—2023年四川省疾病预防控制中心接诊内脏利什曼原虫病病例分析

目的 分析四川省内脏利什曼原虫病病例的流行病学特征,为优化该地区内脏利什曼原虫病的控制措施提供依据。方法 采用内脏利什曼原虫抗体快速检测试剂条(RK39)或骨髓涂片对四川省疾病预防控制中心预防医学门诊部2020—2023年接诊的内脏利什曼原虫病疑似病例进行诊断,收集RK39检测或骨髓涂片阳性指标,采用Excel 2020软件对病例进行描述性流行病学分析。结果 2020—2023年四川省疾病预防控制中心共接诊内脏利什曼原虫病疑似病例325人,确诊36例,阳性率为11.08%。内脏利什曼原虫病男女发病性别比为11∶1;病例分布主要在九寨沟县和黑水县,分别占总病例数的19.44%和11.11%;病例主要以50岁以上农民为主,18岁以下少年儿童病例占比较少;春季、夏季、秋季和冬季内脏利什曼原虫病阳性率分别为10.11%、11.90%、12.99%和9.33%。36例病例中初诊时,仅12例在当地医疗机构确诊为内脏利什曼原虫病,误诊率为66.67%。结论 内脏利什曼原虫病容易误诊和漏诊,应进一步提升基层医疗机构的诊疗水平,长期加强疫区白蛉的防控,加强疫区易感人群的健康教育和防护。