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991.
热蒸加工对大菱鲆过敏原免疫原性的影响 总被引:1,自引:0,他引:1
目的 研究热蒸加工方式对大菱鲆(Scophthatmus maximus)过敏原免疫原性的影响。方法 利用热蒸处理对大菱鲆鱼肉进行了不同时间的加工, 利用SDS-PAGE测定大菱鲆蛋白质组分和蛋白质含量的变化, 并采用免疫印迹和间接ELISA分析热蒸加工对过敏原免疫原性的影响。结果 大菱鲆经过热蒸加工后, 其肌肉组分中分子量在40 ~65 kDa的蛋白有很大程度地降解, 而分子量在10 ~12 kDa的蛋白组分有增加的现象。免疫印迹的结果表明热蒸后的大菱鲆蛋白质组分与血清IgE特异性结合的能力减弱, 但与兔源小清蛋白抗体有强烈地反应, 特别是在分子量18 kDa的位置出现了一条能够与人血清IgE结合的蛋白质, 有可能是新的过敏原组分。结论 热蒸加工可以降低大菱鲆过敏原的免疫活性, 但在加工过程中可能有新的过敏原条带产生, 在进行过敏原检测时有必要考虑加工方式对过敏原结构和活性的影响, 以便得到更可靠的结果。 相似文献
992.
993.
Failure modes and effects analysis for high-power GaN-based light-emitting diodes package technology
Ray-Hua Horng Re-Ching Lin Yi-Chen Chiang Bing-Han Chuang Hung-Lieh Hu Chen-Peng Hsu 《Microelectronics Reliability》2012,52(5):818-821
In this study, nondestructive test is developed to analyze the structure failure of LED package. The relationship between thermal resistance analysis and LED package failure structure is build with T3Ster thermal transient tester and scanning electron microscope (SEM). The failure LED device with defect in the attaching layer and gap between LED chip and copper are designed advisedly. The failure factors of LED package have been measured with thermal resistance analysis and SEM cross-section images. The thermal dissipation performance of LED with defect in the attaching layer is indicated by thermal resistance analysis combined with SEM cross-section images. The blister in attaching layer results in 4.4 K/W additional thermal resistance. The gap between LED chip and copper also makes high additional thermal resistance with 8.6 K/W. Different failures of LED packages are indicated obviously using thermal transfer analysis. The LED package failure structure such as interface defect between solder and cup-shaped copper is able to forecast without destructive measurement. 相似文献
994.
Manganese-doped zinc oxide (Mn-doped ZnO) thin films were prepared using chemical bath deposition (CBD), and the impacts of
the manganese dopant concentration on the structure, electrical resistivity, optical transmission, and magnetic properties
were investigated using x-ray diffractometry, Hall-effect measurements, ultraviolet–visible–near-infrared (UV–Vis–IR) spectrophotometry,
and vibrating sample magnetometry (VSM), respectively. The concentration of the manganese dopant in the ZnO thin film critically
impacted the resulting properties, and the 4.0 at.% Mn-doped ZnO film had a resistivity of 5.8 × 10−2 Ωcm, transmittance of 75.6% in the visible light range, and bandgap of 3.30 eV when the film was annealed at 600°C in an
Ar + H2 atmosphere. Annealing the film could enhance its magnetic properties such that the film had a saturation magnetization of
21.0 emu/cm3 and a coercivity of 45.7 Oe after annealing at 600°C. Because of these electrical, optical, and magnetic properties, Mn-doped
thin films are promising for use in spintronic devices. 相似文献
995.
Low-voltage-differential-signaling (LVDS) is one of the very popular technologies which simultaneously addresses low dynamic power consumption and high data rate transmission in modern high speed circuit applications. In this paper, system level integration design approach is applied to design LVDS transmitter featuring high off-chip data rate. Full wave electromagnetic simulation technique was adopted to accurately characterize possible couplings and parasitic effects induced from the off-chip components which then acted as the termination of the output circuitry. Common mode feedback was included to perform fine tuning on the offset leading to much higher overall precision. Meanwhile, generation of the controlled current and voltage across termination was guaranteed through the introduction of a constant transconductance bias network. The design was implemented using TSMC 3.3?V 0.35???m CMOS technology with overall chip size of 0.923?mm2. At a DC power consumption level of 29.4?mW, the LVDS transmitter exhibited an off-chip data rate of 1.3?Gb/s validated through measurements. 相似文献
996.
Chin‐Ling Chen Cheng‐Chi Lee Chao‐Yung Hsu 《International Journal of Communication Systems》2012,25(5):585-597
Various user authentication schemes with smart cards have been proposed. Generally, researchers implicitly assume that the contents of a smart card cannot be revealed. However, this is not true. An attacker can analyze the leaked information and obtain the secret values in a smart card. To improve on this drawback, we involve a fingerprint biometric and password to enhance the security level of the remote authentication scheme Our scheme uses only hashing functions to implement a robust authentication with a low computation property. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
997.
Sui-Ying Hsu Chih-Hung Tsai Chun-Yang Lu Yu-Tang Tsai Tsung-Wei Huang Yuan-Hsuan Jhang Yan-Fang Chen Chung-Chih Wu Yen-Shan Chen 《Organic Electronics》2012,13(5):856-863
We report an effective way to produce nanoporous Pt counter electrodes of dye-sensitized solar cells by the glancing-angle deposition (GLAD) technique. By controlling the orientation of the substrate relative to the incident Pt vapor flux during the deposition, nanoporous films composed of inclined nm-scale columns were produced through the self-shadowing effect. Pt counter electrodes having varied nanoporous structures were characterized for their morphological and electrochemical properties, and were subjected to device studies to establish the correlation with DSSC characteristics/performances. The results suggest that the nanoporous GLAD Pt electrodes can effectively enhance active surface areas, the catalytic ability and charge exchange at the Pt/electrolyte interface of a DSSC. As a result, the quantum efficiency, short-circuit current, and power conversion efficiency of the DSSC can be enhanced by up to 12–13% with using the nanoporous GLAD Pt counter electrodes. 相似文献
998.
Jhong‐Sian Wu Yen‐Ju Cheng Tai‐Yen Lin Chih‐Yu Chang Peng‐I. Shih Chain‐Shu Hsu 《Advanced functional materials》2012,22(8):1711-1722
A new class of ladder‐type dithienosilolo‐carbazole ( DTSC ), dithienopyrrolo‐carbazole ( DTPC ), and dithienocyclopenta‐carbazole ( DTCC ) units is developed in which two outer thiophene subunits are covalently fastened to the central 2,7‐carbazole cores by silicon, nitrogen, and carbon bridges, respectively. The heptacyclic multifused monomers are polymerized with the benzothiadiazole ( BT ) acceptor by palladium‐catalyzed cross‐coupling to afford three alternating donor‐acceptor copolymers poly(dithienosilolo‐carbazole‐alt‐benzothiadiazole) ( PDTSCBT) , poly(dithienocyclopenta‐carbazole‐alt‐benzothiadiazole) ( PDTCCBT), and poly(dithienopyrrolo‐carbazole‐alt‐benzothiadiazole) ( PDTPCBT) . The silole units in DTSC possess electron‐accepting ability that lowers the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of PDTSCBT , whereas stronger electron‐donating ability of the pyrrole moiety in DTPC increases the HOMO and LUMO energy levels of PDTPCBT . The optical bandgaps (Egopt) deduced from the absorption edges of thin film spectra are in the following order: PDTSCBT (1.83 eV) > PDTCCBT (1.64 eV) > PDTPCBT (1.50 eV). This result indicated that the donor strength of the heptacyclic arenes is in the order: DTPC > DTCC > DTSC . The devices based on PDTSCBT and PDTCCBT exhibited high hole mobilities of 0.073 and 0.110 cm2 V?1 s?1, respectively, which are among the highest performance from the OFET devices based on the amorphous donor‐acceptor copolymers. The bulk heterojunction photovoltaic device using PDTSCBT as the p‐type material delivered a promising efficiency of 5.2% with an enhanced open circuit voltage, Voc, of 0.82 V. 相似文献
999.
Mahmood AHMAD Xiao-Wei TANG Jiang-Nan QIU Feezan AHMAD Wen-Jing GU 《Frontiers of Structural and Civil Engineering》2020,14(6):1476
The unprecedented liquefaction-related land damage during earthquakes has highlighted the need to develop a model that better interprets the liquefaction land damage vulnerability (LLDV) when determining whether liquefaction is likely to cause damage at the ground’s surface. This paper presents the development of a novel comprehensive framework based on select case history records of cone penetration tests using a Bayesian belief network (BBN) methodology to assess seismic soil liquefaction and liquefaction land damage potentials in one model. The BBN-based LLDV model is developed by integrating multi-related factors of seismic soil liquefaction and its induced hazards using a machine learning (ML) algorithm-K2 and domain knowledge (DK) data fusion methodology. Compared with the C4.5 decision tree-J48 model, naive Bayesian (NB) classifier, and BBN-K2 ML prediction methods in terms of overall accuracy and the Cohen’s kappa coefficient, the proposed BBN K2 and DK model has a better performance and provides a substitutive novel LLDV framework for characterizing the vulnerability of land to liquefaction-induced damage. The proposed model not only predicts quantitatively the seismic soil liquefaction potential and its ground damage potential probability but can also identify the main reasons and fault-finding state combinations, and the results are likely to assist in decisions on seismic risk mitigation measures for sustainable development. The proposed model is simple to perform in practice and provides a step toward a more sophisticated liquefaction risk assessment modeling. This study also interprets the BBN model sensitivity analysis and most probable explanation of seismic soil liquefied sites based on an engineering point of view. 相似文献
1000.
Yen‐Hsu CHEN Wu‐Chang YANG Feng‐Ming WANG Der‐Cherng TARNG Jinn‐Yang CHEN Yee‐Yung NG Tsai‐Hun WU Yao‐Ping LIN Chih‐Ching LIN 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(1):79-86
Elevated levels of serum pancreatic enzymes are frequently observed in hemodialysis (HD) patients. The complex hemodynamic, biochemical, and physiological alterations in uremia were speculated to cause excessive release of pancreatic enzymes beyond decreased renal clearance. However, hemodynamic factors are seldom explored in this aspect. We performed the study to evaluate the association between intradialytic hemodynamic change and elevated serum pancreatic amylase (SPA). Eighty‐three prevalent HD patients without any clinical evidence of acute pancreatitis underwent pre‐HD and post‐HD blood sampling for serum pancreatic enzyme levels. Demographic, biochemical, and hematological data were collected from patient record review. Hemodialysis information including intradialytic blood pressure changes and ultrafiltration (UF) amount were collected and averaged for 1 month before the blood sampling day. Patients with elevated SPA during the HD session had greater mean systolic blood pressure and mean arterial pressure reduction, greater UF volume, greater pre‐HD blood urea nitrogen and serum creatinine, higher serum phosphorus, lower pre‐HD serum total CO2, and lower left ventricle ejection fraction (LVEF). Using multivariate linear and logistic regression analysis, the independent predictors of elevated SPA were determined to be mean arterial pressure reduction during HD, mean UF amount, pre‐HD serum total CO2, and LVEF. Greater blood pressure reduction during HD, greater UF volume, lower pre‐HD serum total CO2, and lower LVEF were significantly associated with elevated SPA during HD. This suggests that hemodynamic factors contribute to elevated serum pancreatic enzymes in HD patients. 相似文献