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41.
卫星包装箱的随机隔振优化分析   总被引:1,自引:0,他引:1  
田千里  许滨 《包装工程》1991,12(2):52-57
用钢丝绳隔振器将卫星包装箱支承在运输车上,将卫星与车辆简化为二自由度体系,优化分析了在随机路面上行驶时使包装箱响应最小之隔振参数,对实测得到的钢丝绳减振器的非线性迟滞性能作了描述,提出了统计线性化分析的方法。  相似文献   
42.
气垫性能及平板玻璃缓冲包装   总被引:4,自引:4,他引:0  
对我国发明的缓冲包装气垫进行静态试验,测其载荷-变形曲线,表明它属于正切型;对气垫作为内衬的PZOV型平板玻璃包装件进行冲击和振动试验,证明具有优良的防震缓冲性能,适于平板玻璃的运输包装。  相似文献   
43.
饮料包装的计算机控制和管理   总被引:1,自引:1,他引:0  
于平 《包装工程》1992,13(2):66-69
着重介绍计算机技术在饮料包装方面应用的发展情况,灌装生产流水线的计算机控制和管理,自动装卸搬运系统和计算机仓库管理系统等。  相似文献   
44.
A panel of experienced assessors was used to test the effect of irradiation at 2.5kGy (250krad) on the sensory quality of 1-day and 21-day-old turkey breast fillets stored at 1°C in either oxygen-permeable polythene or an oxygen-impermeable barrier film. In the application of Free Choice Profiling and Generalized Procrustes Analysis, assessors used their own terms to describe the appearance, odour and flavour of the samples.
The irradiated samples showed negligible growth of micro-organisms across 21 days of storage. Radiation treatment resulted in an intense pink colour in the raw and cooked samples, which was maintained during storage in oxygen-impermeable film, but decreased in samples exposed to oxygen during storage. Radiation also produced a set of unpleasant raw odour notes variously described as sour, rancid, mature, bad meat or putrid in the samples stored in oxygen-impermeable film. These notes were unlike the sulphurous notes previously associated with protein denaturation in irradiated chicken and were apparently distinct from the odour notes that developed in corresponding non-irradiated samples.  相似文献   
45.
Reduced ascorbic acid (RAA) content, total chlorophyll and green color retention, enzyme activities and texture changes were followed in broccoli spears packaged in polymeric film and nonpackaged during 96 hr storage (10°C). Concentrations within packages monitored by gas chromatography were (CO2,) 8% and (02) 10%. RAA retention, moisture content, total chlorophyll and color retention were greater in packaged broccoli. No differences were found between packaged and nonpackaged broccoli for ascorbate oxidase and peroxidase activities, or texture.  相似文献   
46.
We investigated pasteurization and storage of blue crabmeat in steel cans, aluminum cans, plastic cans, nonbarrier pouches, and barrier pouches. Fresh meat was packed in copolymer polyethylene/polypro-pylene cups, Saran® over-wrapped or vacuum skin packaged polystyrene trays, and nonbarrier pouches. Meat pasteurized in plastic and aluminum cans had better sensory and microbiological quality and longer shelf life than meat packed in steel cans. Oxygen-barrier pouches had the lowest quality and shortest shelf life. Nonbarrier pouches had product with quality similar to meat in steel cans, but with an extended shelf life. No packaging materials improved the microbiological shelf life of freshly cooked meat. Vacuum skin packaging resulted in improved sensory qualities of freshly cooked and picked meat.  相似文献   
47.
A unique substrate MCPM (Mitsubishi Copper Polyimide Metal-base) technology has been developed by applying our basic copper/polyimide technology.1 This new substrate technology MCPM is suited for a high-density, multi-layer, multi-chip, high-power module/package, such as used for a computer. The new MCPM was processed using a copper metal base (110 × 110 mm), full copper system (all layers) with 50-μm fine lines. As for pad metallizations for the IC assembly, we evaluated both Ni/Au for chip and wire ICs and solder for TAB ICs. The total number of assembled ICs is 25. To improve the thermal dispersion, copper thermal vias are simultaneously formed by electro-plating. This thermal via is located between the IC chip and copper metal base, and promotes heat dispersion. We employed one large thermal via (4.5 mm?) and four small vias (1.0 mm?) for each IC pad. The effect of thermal vias and/or base metal is simulated by a computer analysis and compared with an alumina base substrate. The results show that the thermal vias are effective at lowering the temperature difference between the IC and base substrate, and also lowering the temperature rise of the IC chip. We also evaluated the substrate’s reliability by adhesion test, pressure cooker test, etc.  相似文献   
48.
印明奎 《电焊机》1994,(4):37-41
本文对不同种类、结构、工作条件、制造质量压力容器的缺陷检测处理和现场补焊修复的原则和工艺作了详细的叙述。  相似文献   
49.
The shear strength and aging characteristics of 63Sn–37Pb solder bumps were characterized with variation in solder ball and UBM pad sizes. The shear strength increased with shorter effective crack size,a effs which was determined with the solder ball and pad sizes. The shear strength of the solder bumps on Au/Ni/Cu and Ni/Cu did not change significantly with reflow time. Substantial decrease in the shear strength occurred for the solder bumps formed on Au/Ni/Cu with aging treatment, and the shear strength after aging was also related to the bump shape which was determined with the solder ball and pad sizes.  相似文献   
50.
赵小艳  陈良伦  何清玉 《安徽化工》2004,30(6):13-15,18
说明了水基传送带润滑剂的作用机理、性能要求,详细介绍了现有的水基传送带润滑剂的特点,并简单介绍了水基传送带润滑剂的发展前景和趋势。  相似文献   
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