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91.
CHENG Jianwei SHI Yun WANG Youjie YE Linxiang ZHOU Yikai.State Environmental Protection Administration of China 《国外医学:社会医学分册》2006,(4)
提出环境污染健康损害判定工作程序及步骤,给出已知污染物或未知污染物造成健康损害判定工作框图,并提出健康损害判定:①必须经环境保护主管部门进行资质认定的环境污染健康损害判定机构承担;②具有健康损害判定资质的机构应建立相应专家组;③健康损害判定专家组按相关标准根据医学诊断、环境证据及因果关系进行健康损害判定。 相似文献
92.
Dariusz Ulbrich Arkadiusz Stachowiak Jakub Kowalczyk Daniel Wieczorek Waldemar Matysiak 《Materials》2022,15(11)
The article presents the results of research on abrasive and tribocorrosion wear of boron steel. This type of steel is used in the automotive and agricultural industries for the production of tools working in soil. The main goal of the article is the evaluation of tribocorrosion and abrasive wear for hot-formed 22MnCrB5 steel and a comparison of the obtained results with test results for steel in a cold-formed state. The spinning bowl method to determine the wear of samples working in the abrasive mass was used. Furthermore, a stand developed based on the ball-on-plate system allows to determine the wear during the interaction of friction and corrosion. After the hot-forming process, 22MnCrB5 steel was three times more resistant for the abrasive wear than steel without this treatment. The average wear intensity for 22MnCrB5 untreated steel was 0.00046 g per km, while for 22MnCrB5 hot-formed steel it was 0.00014 g per km. The tribocorrosion tests show that the wear trace of hot-formed 22MnCrB5 steel was about 7.03 µm, and for cold-formed 22MnCrB5 steel a 12.11 µm trace was noticed. The hot-forming method allows to obtain the desired shape of the machine element and improves the anti-wear and anti-corrosion properties for boron steel. 相似文献
93.
Yongming Yan Yanjun Xue Wenchao Yu Ke Liu Maoqiu Wang Xinming Wang Liuqing Ni 《Materials》2022,15(12)
This paper focuses on the effect of gear steel on distortion due to phase transformation in carburizing and quenching. The carburizing and quenching process of C-rings under suspension was studied by using the finite element method based on the thermo-mechanical theory, considering phase transformation. The phase transformation kinetics parameters, depending on different carbon contents, were measured by Gleeble-3500. The distortion behavior of the carburized C-ring during the cooling stage was analyzed, as well as the carbon concentration distribution and martensite volume fractions. The accuracy of the simulation was also verified by comparing the experimental data with the simulated result of the distortion and microstructure. A reliable basis is provided for predicting the distortion mechanism of gear steels in carburizing and quenching. 相似文献
94.
To obtain the tire–pavement peak adhesion coefficient under different road states, a field measurement and FE simulation were combined to analyze the tire–pavement adhesion characteristics in this study. According to the identified texture information, the power spectral distribution of the road surface was obtained using the MATLAB Program, and a novel tire hydroplaning FE model coupled with a textured pavement model was established in ABAQUS. Experimental results show that here exists an “anti-skid noncontribution area” for the insulation and lubrication of the water film. Driving at the limit speed of 120 km/h, the critical water film thickness for the three typical asphalt pavements during hydroplaning was as follows: AC pavement, 0.56 mm; SMA pavement, 0.76 mm; OGFC pavement, 1.5 mm. The road state could be divided into four parts dry state, wet sate, lubricated state, and ponding state. Under the dry road state, when the slip rate was around 15%, the adhesion coefficient reached the peak value, i.e., around 11.5% for the wet road state. The peak adhesion coefficient for the different asphalt pavements was in the order OGFC > SMA > AC. This study can provide a theoretical reference for explaining the tire–pavement interactions and improving vehicle brake system performance. 相似文献
95.
Galina V. Kurlyandskaya Luis Lezama Anna A. Pasynkova Stanislav O. Volchkov Vera A. Lukshina Aitor Larraaga Natalia V. Dmitrieva Anastasia V. Timofeeva Iaki Orue 《Materials》2022,15(12)
The ferromagnetic resonance (FMR) in the frequency range of 0.5 to 12.5 GHz has been investigated as a function of external magnetic field for rapidly quenched Fe3Co67Cr3Si15B12 amorphous ribbons with different features of the effective magnetic anisotropy. Three states of the ribbons were considered: as-quenched without any treatment; after relaxation annealing without stress at the temperature of 350 °C during 1 h; and after annealing under specific stress of 230 MPa at the temperature of 350 °C during 1 h. For FMR measurements, we adapted a technique previously proposed and tested for the case of microwires. Here, amorphous ribbons were studied using the sample holder based on a commercial SMA connector. On the basis of the measurements of the reflection coefficient S11, the total impedance including its real and imaginary components was determined to be in the frequency range of 0.5 to 12.5 GHz. In order to confirm the validity of the proposed technique, FMR was also measured by the certified cavity perturbation technique using a commercial Bruker spectrometer operating at X-band frequency of 9.39 GHz. As part of the characterization of the ribbons used for microwave measurements, comparative analysis was performed of X-ray diffraction, optical microscopy, transmission electron microscopy, inductive magnetic hysteresis loops, vibrating sample magnetometry, magneto-optical Kerr effect (including magnetic domains) and magnetoimpedance data for of all samples. 相似文献
96.
[目的] 利用Box-Behnken响应面设计法优化中药复方便乃通(BNT)的提取工艺。[方法] 基于单因素实验优选BNT提取工艺的影响因素及其范围,运用Box-Behnken响应面设计法构建三因素三水平实验设计方案,以番泻苷B、番泻苷A及橙皮苷的含量作为响应指标优选最佳提取工艺条件,并进行工艺验证。[结果] 中药复方BNT的最佳提取工艺条件为料液比1∶8,回流时间30 min,提取次数2次。[结论] 利用Box-Behnken响应面设计法优化中药复方BNT提取工艺方法稳定,可为BNT提取工艺提供参考。 相似文献
97.
Sabine Hummel Katharina Obermeier Katja Zier Sandra Krommes Michael Schemme Peter Karlinger 《Materials》2022,15(11)
Increasing demand for energy-efficient means of transport has steadily intensified the trend towards lightweight components. Thermoplastic glass fiber composites (organo sheets) play a major role in the production of functional automotive components. Organo sheets are cut, shaped and functionalized by injection molding to produce hybrid components, such as those used in car door modules. The cutting process produces a considerable amount of production waste, which has thus far been thermally recycled. This study develops a closed mechanical recycling process and analyzes the different steps of the process. The offcuts were shredded using two shredding methods and implemented directly in the injection-molding process. Using tensile tests and impact bending tests, the material properties of the recycled materials were compared with the virgin material. In addition, fiber length degradation via the injection-molding process and the influence of the waterjet-cutting process on the mechanical properties are investigated. Recycled offcuts are both comparable to new material in terms of mechanical properties and usability, and are also economically and ecologically advantageous. Recycling polypropylene waste with glass fiber reinforcement in a closed loop is an effective way to reduce industrial waste in a sustainable and economical production process. 相似文献
98.
马青山 《中国医院建筑与装备》2009,(8):55-56
医院实验室内存放了大量设备、仪器,一旦在地震中倒塌,经济损失巨大,设计师必须对实验室的抗震设计特别是结构设计引起更多的重视。 相似文献
99.
目的 优选紫红生肌软膏的醇提工艺参数,为紫红生肌软膏的新药开发提供依据.方法 以栀子苷、连翘酯苷A、羟基红花黄色素A为评价指标,在单因素试验的基础上,以乙醇浓度、加醇量、提取时间为考察因素,采用Box-behnken响应面法设计试验,采用层次分析法-熵权法组合赋权确定各指标权重系数并计算综合评分,从而优化紫红生肌软膏醇... 相似文献
100.
文章以山东烟台芝罘区南部新城医院为例,从出入口设置、整体布局、功能分区、景观绿化、外形设计等方面介绍了集多种医疗功能于一体的医院建筑的设计方法和思路。 相似文献