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991.
G. Gregoris F. Bouton C. De Keukeleire P. Siliprandi F. Baio L. De Schepper W. De Ceuninck L. Tielemans T. Ahrens M. Krumm 《Quality and Reliability Engineering International》1996,12(4):247-252
We present the results of SHORTEST, a BRITE EURAM II project for the introduction in industry of an advanced approach to the reliability evaluation of electronic assemblies. The achievements so far are the development and validation of seven in-situ test techniques. Five of the test techniques demonstrate the capability of detecting failure mechanisms at 48 hours with moderate stress conditions, and half of the in-situ test results obtained at 48 hours on 10 subtechnologies correlate with conventional tests. All correlation results are presented. The application of the method for quality assurance and building-in reliability is discussed. The final aim of SHORTEST is to look for the exploitation of the developed in-situ techniques. The marketing study that will define the industrial needs of European companies is presented. In parallel, the insertion in the CECC specification of recommendations based on the SHORTEST principle is foreseen. 相似文献
992.
993.
994.
A. G. C. Machiels K. F. J. Denys J. Van Dam A. Posthuma De Boer 《Polymer Engineering and Science》1996,36(19):2451-2466
This paper describes the preparation and properties of in-situ composites based on polymers with no overlap in processing temperatures. The polymers used were Vectra A900, a thermotropic liquid crystalline copolyester (TLCP), and Arnitel em630, a thermoplastic elastomer. Blends were generated by feeding the two components from separate extruders into a Ross static mixer. Different morphologies were obtained by varying the number of mixing elements of the static mixer. Using 8 mixing elements led to a stratified morphology of Vectra layers in Arnitel, using 11 mixing elements resulted in the desired continuous fiber/matrix morphology whereas a pronounced skin-core morphology was obtained with 14 mixing elements. It is argued that in-situ composites can be generated by a distributive mixing process without the formation of an intermediate droplet/matrix morphology as occurs in common dispersive blending equipment. Tensile modulus and strength of all blends increased with extrudate draw ratio as a result of increased molecular orientation of the TLCP phase. The level of reinforcement, however, was lower than expected, probably due to the low temperature of drawing. Annealing and capillary instability experiments showed that above the melting point of the TLCP the fiber/matrix morphology rapidly breaks up into a droplet/matrix morphology. This process takes just a few seconds for fibers of thickness ∼ 1 μm. It is shown to be the probable cause of the skin-core morphology obtained in case of 14 mixing elements. 相似文献
995.
为了研究养心菜的加工适用性,拓展其利用途径,采用未预处理(Untreated,UT)、沸水漂烫(Boiling Water Blanching,BWB)、沸水+护色漂烫(COLOR Protection+Water Blanching,CPB)、蒸汽漂烫(Steam Blanching,SB)与冻融(Freeze-Thawing,FT)五种预处理方式处理后,分别进行热风干燥(Hot Air Drying,HA)、热泵干燥(Heat Pump Drying,HP),得到UT HP、UT HA、BWB HP、BWB HA、CPB HP、CPB HA、SB HP、SB HA、FT HP及FT HA 10种养心菜粉,比较不同预处理方式和干燥方式下养心菜色泽、功能成分及抗氧化能力水平的变化。结果表明:UT HP没食子酸和山萘酚含量最高,但色泽差、叶绿素含量较低,干燥时间长;CPB HP的干燥时间短,Vc含量最高,具有较高的抗氧化水平,但没食子酸含量较低;SB HP总酚、总黄酮、槲皮素含量最高,其他品质指标介于中间;FT HP养心菜具有最好的色泽、最高的叶绿素、游离氨基酸含量,但总酚、总黄酮、槲皮素、山萘酚以及抗氧化水平低。从主成分分析来看,BWB HP、CPB HP、SB HP 和BWB HA、CPB HA、SB HA的养心菜品质分别具有一定的相似性,UT HP、FT HP、UT HA、UT HA和其有明显差异。该文综合比较了养心菜不同预处理及干燥方法的优劣,在养心菜下游的功能性食品的开发过程中,可以根据需求选择合适的干燥方法。 相似文献
996.
997.
Results related to the mechanical properties of in situ composites based on partially miscible blends of polyetherimide (Ultem) and liquid crystalline polymers (HX1000 and HX4000) are discussed. It is observed that, at least in terms of the tensile and flexural modulus, there is a positive deviation from the law of mixtures. These results are analyzed and an attempt is made to explain the origin of this synergistic behavior based upon morphological data. The behavior of these partially miscible systems is compared to that of an immiscible system (Ultem/Vectra) and also that of glass-reinforced Ultem. Using blends subjected to two passes through a single screw extruder, and thereby increasing the mixing history of the Ultem/HX4000 blend, led to improved dispersion but did not lead to any measurable improvement, within experimental error, in the tensile modulus or ultimate strength (though the toughness was enhanced). The dynamic creep compliance was measured and the creep behavior with composition and temperature is discussed. The data seem to suggest that a number of factors (including partial miscibility, the properties of the specific LCP chosen as the reinforcement and the final blend morphology) all interact in a complex and as yet undetermined manner to produce the enhanced mechanical properties. 相似文献
998.
A. Cimitile U. De Carlini U. Villano 《Software Testing, Verification and Reliability》1993,3(2):83-100
Parallel programs are intrinsically non-deterministic, and therefore the techniques of cyclical debugging that are commonly used for sequential programs are not suitable for parallel ones. This paper proposes a method to reproduce Occam program behaviour. Saving information on the timer values input by the program and the guards selected at run-time on alternative commands allows program replay, i.e. it makes it possible to re-execute the program deterministically with the same inputs following the same instruction path. This enables the software developer to use tools such as debuggers and intrusive monitors to help identify program faults. After discussing possible implementations of the proposed technique, IRD (an interactive replay debugger for Occam programs) is described. Finally, the use of the IRD in a sample debug session is presented as an example. 相似文献
999.
Maria Lucia Iacovino Chiara Carmen Miceli Marco De Felice Biagio Barone Luca Pompella Francesco Chiancone Erika Di Zazzo Giuseppe Tirino Carminia Maria Della Corte Ciro Imbimbo Ferdinando De Vita Felice Crocetto 《International journal of molecular sciences》2022,23(3)
Muscle invasive bladder cancer (MIBC) is a widespread malignancy with a worse prognosis often related to a late diagnosis. For early-stage MIBC pts, a multidisciplinary approach is mandatory to evaluate the timing of neoadjuvant chemotherapy (NAC) and surgery. The current standard therapy is platinum-based NAC (MVAC-methotrexate, vinblastine, doxorubicin, and cisplatin or Platinum–Gemcitabine regimens) followed by radical cystectomy (RC) with lymphadenectomy. However, preliminary data from Vesper trial highlighted that dose-dense NAC MVAC is endowed with a good pathological response but shows low tolerability. In the last few years, translational-based research approaches have identified several candidate biomarkers of NAC esponsiveness, such as ERCC2, ERBB2, or DNA damage response (DDR) gene alterations. Moreover, the recent consensus MIBC molecular classification identified six molecular subtypes, characterized by different sensitivity to chemo- or targeted or immunotherapy, that could open a novel procedure for patient selection and also for neoadjuvant therapies. The Italian PURE-01 phase II Trial extended data on efficacy and resistance to Immune Checkpoint Inhibitors (ICIs) in this setting. In this review, we summarize the most relevant literature data supporting NAC use in MIBC, focusing on novel therapeutic strategies such as immunotherapy, considering the better patient stratification and selection emerging from novel molecular classification. 相似文献
1000.
Piero Portincasa Leonilde Bonfrate Mirco Vacca Maria De Angelis Ilaria Farella Elisa Lanza Mohamad Khalil David Q.-H. Wang Markus Sperandio Agostino Di Ciaula 《International journal of molecular sciences》2022,23(3)
Gut microbiota encompasses a wide variety of commensal microorganisms consisting of trillions of bacteria, fungi, and viruses. This microbial population coexists in symbiosis with the host, and related metabolites have profound effects on human health. In this respect, gut microbiota plays a pivotal role in the regulation of metabolic, endocrine, and immune functions. Bacterial metabolites include the short chain fatty acids (SCFAs) acetate (C2), propionate (C3), and butyrate (C4), which are the most abundant SCFAs in the human body and the most abundant anions in the colon. SCFAs are made from fermentation of dietary fiber and resistant starch in the gut. They modulate several metabolic pathways and are involved in obesity, insulin resistance, and type 2 diabetes. Thus, diet might influence gut microbiota composition and activity, SCFAs production, and metabolic effects. In this narrative review, we discuss the relevant research focusing on the relationship between gut microbiota, SCFAs, and glucose metabolism. 相似文献