Effects of separator breakdown on abuse response of 18650 Li-ion cells

The thermal abuse tolerance of Li-ion cells depends not only on the stability of the active materials in the anode and cathode but also on the stability of the separator which prevents direct interaction between these electrodes. Separator response has been measured as a function of temperature and high voltage both for isolated materials and in full 18650 cells. Separators with different compositions and properties were measured to determine the effect of separator melt integrity on cell response under abusive conditions. These studies were performed as part of the U.S. Department of Energy (DOE) Advanced Technology Development (ATD) Program.     

沉桩挤土效应研究综述

从理论及试验研究两方面对前人在沉桩挤土效应方面的研究成果进行综述,建立了沉桩挤土效应研究的系统构架,对该课题在今后的研究内容、发展方向等方面给出了建议.     

A genome-wide screen for susceptibility loci in ankylosing spondylitis

OBJECTIVE: To localize the regions containing genes that determine susceptibility to ankylosing spondylitis (AS). METHODS: One hundred five white British families with 121 affected sibling pairs with AS were recruited, largely from the Royal National Hospital for Rheumatic Diseases AS database. A genome-wide linkage screen was undertaken using 254 highly polymorphic microsatellite markers from the Medical Research Council (UK) (MRC) set. The major histocompatibility complex (MHC) region was studied more intensively using 5 microsatellites lying within the HLA class III region and HLA-DRB1 typing. The Analyze package was used for 2-point analysis, and GeneHunter for multipoint analysis. RESULTS: When only the MRC set was considered, 11 markers in 7 regions achieved a P value of < or =0.01. The maximum logarithm of odds score obtained was 3.8 (P = 1.4 x 10(-5)) using marker D6S273, which lies in the HLA class III region. A further marker used in mapping of the MHC class III region achieved a LOD score of 8.1 (P = 1 x 10(-9)). Nine of 118 affected sibling pairs (7.6%) did not share parental haplotypes identical by descent across the MHC, suggesting that only 31% of the susceptibility to AS is coded by genes linked to the MHC. The maximum non-MHC LOD score obtained was 2.6 (P = 0.0003) for marker D16S422. CONCLUSION: The results of this study confirm the strong linkage of the MHC with AS, and provide suggestive evidence regarding the presence and location of non-MHC genes influencing susceptibility to the disease.     

实时MR成像引导下猪脑动脉导管插管的实验研究

目的探讨实时MR成像引导下在猪脑动脉内进行导管插管的可行性。方法选用１０只美国产的雌性小型猪作为实验对象。经皮穿刺股动脉,在实时MR成像引导下,将３F主动追踪微导管分别插至双侧咽升动脉内。解剖其主动脉弓、头臂动脉、颈动脉和咽升动脉,用肉眼观察有无穿孔、夹层等损害。结果MR血管成像证实,猪主要由双侧咽升动脉在颅底形成微血管网供应脑的血供。在实时MR（rtMR）成像引导下,对１０只猪双侧咽升动脉进行插管操作,均操作成功,单次操作费时为４～１２min。所有实验动物的主动脉弓、头臂动脉、颈动脉和咽升动脉的内壁均光滑完整,未发现血管壁损伤。结论实时MR成像引导下,可以将导管迅速、准确地插至猪脑动脉。     

Convenient synthesis of mosquito oviposition pheromone and a highly fluorinated analog retaining biological activity

A simple three-step synthesis is described for 6-acetoxy-5-hexadecanolide, the oviposition pheromone of the mosquitoCulex quinquefasciatus Say and others in that genus. An aldol condensation between 1-trimethylsilyloxycyclopent-1-ene and undecanal, followed by Baeyer-Villiger ring expansion and acetylation, gave the required compound as a 1∶1 mixture of diastereoisomers in high overall yield (>80%). This synthetic approach is readily adapted for synthesis of analogs. The heptadecafluoro compound, in which then-octyl group is replaced by perfluorooctyl, retained high biological activity.     

Solidification and microstructure of a high alloy stainless steel

The steel considered in the present work can be classified as a 6Mo austenitic stainless steel, which has a much higher corrosion resistance than many other commercially available stainless steels. However, because of macrosegregation during solidification of ingot casting, the high alloy content in the steel, especially Mo, N, C, enhances precipitation of intermetallic phases such asa phase. Such precipitation mainly occurs in the center of the material and has normally no significant effect on mechanical properties or surface corrosion resistance. The introduction of modern production methods such as continuous casting of slabs for stainless sheet production has reduced the macrosegregation tendency and related precipitation. However, the microsegregation in a small scale may be enhanced as the higher cooling rate prevents the diffusion in the solidified region. In the present work, the continuous casting solidification process was simulated in a laboratory gradient     

Aspirin-induced asthma and HLA-DRB1 and HLA-DPB1 genotypes

BACKGROUND: Aspirin-induced asthma (AIA) affects one in 10 individuals with adult-onset asthma. It is not known if aspirin sensitivity is due to immune mechanisms or to interference with biochemical pathways. OBJECTIVE: The study aimed to test for possible involvement of the genes of the Major Histocompatibility Complex (MHC) in AIA. METHODS: HLA-DPB1 and HLA-DRB1 genotyping was carried out by DNA methods in 59 patients with positive challenge tests for AIA and in 48 normal and 57 asthmatic controls. RESULTS: The DPB1*0301 frequency was increased in AIA patients when compared with normal controls (19.5% vs 5.2%, Odds Ratio = 4.4, 95% Confidence Interval (CI) 1.6-12.1, P = 0.002), and compared with asthmatic controls (4.4%, OR = 5.3, 95% CI = 1.9-14.4, P = 0.0001). The frequency of DPB1*0401 in AIA subjects was decreased when compared with normal controls (28.8% vs 49.0%, OR = 0.42, 95% CI = 0.24-0.74, P = 0.003) and asthmatic controls (45.6%, OR = 0.48, 95% CI = 0.28-0.83, P = 0.008). The results remained significant when corrected for multiple comparisons. There were no significant HLA-DRB1 associations with AIA. CONCLUSION: The presence of an HLA association suggests that immune recognition of an unknown antigen may be part of the aetiology of AIA.     

钢纤维混凝土五桩承台中间桩受力研究

通过试验研究,对五桩承台中间桩和角桩进行受力分析,着重探索五桩承台中间桩随承台厚度变化的受力机理,并利用ANSYS对钢纤维混凝土五桩承台进行有限元验算分析,探讨其在实际工程中的应用.