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排序方式: 共有8041条查询结果,搜索用时 225 毫秒
41.
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
42.
饮料包装的计算机控制和管理 总被引:1,自引:1,他引:0
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
43.
J. A. LYNCH H. J. H. MACFIE† G. C. MEAD‡ 《International Journal of Food Science & Technology》1991,26(6):653-668
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
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
44.
Modified Atmosphere Packaging Affects Ascorbic Acid, Enzyme Activity and Market Quality of Broccoli 总被引:1,自引:0,他引:1
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
45.
KEITH W. GATES AMANDA H. PARKER DIANA L. BAUER YAO-WEN HUANG 《Journal of food science》1993,58(2):314-317
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
46.
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
47.
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
48.
49.
塑料在包装领域有着广泛的应用,其中聚酯(PET)性能优良,应用领域不断扩大。介绍了塑料包装不断通现的新技术,以及塑料包装环保问题的几点思路。 相似文献
50.
Francis W. Maloba Michael L. Rooney Paul Wormell Minh Nguyen 《Journal of the American Oil Chemists' Society》1996,73(2):181-185
The oxidative stability of sunflower oil (SFO) was measured during storage at 23 and 37°C in the presence of a novel oxygen-scavenging
film that contained polyfuryloxirane (PFO). Commercially refined and deodorized SFO was stored in a lighted room in sealed
transparent packages containing either PFO film or an antioxidant, 0.02% butylated hydroxytoluene (BHT). Oxidative stability
was evaluated by determination of peroxide values and gas-chromatographic measurement of headspace hexanal. SFO stored in
the presence of the oxygen-scavenging film was more stable than oil stored without the film, or than film stored with 0.02%
BHT. The PFO film scavenges oxygen through energy-transfer sensitization of singlet oxygen. The film is doped with eosin and
the naturally-occurring dye, curcumin, which absorb over a wide range of visible wavelengths. Curcumin transfers its absorbed
energy to eosin, which sensitizes the production of singlet oxygen. The singlet oxygen is scavenged by PFO. The use of two
dyes increases the efficiency of the sensitization process, reducing the illumination time and intensity required for effective
oxygen scavenging. 相似文献