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91.
正集聚的目的是使纤维在即将加捻之前彼此既平行又非常接近地排列,这种设置纤维的方式将使集聚纺纱具有其特有的性能,纺纱三角区的消除仅仅是这种设置的一个结果。以下尝试解释在集聚区发生的实际情况。所有成功的集聚纺纱系统都具有以下特点:a)在正常的三罗拉牵伸系统的出口与钳口线之间有一个集聚区;b)这个区域由一个带集聚槽的吸风管组成,集聚槽倾斜于纱线路径的方向,集聚槽内施加了负压;c)一个带网眼器材的输送方法(如网格圈或  相似文献   
92.
The influence of trypsin action in yoghurt milk on the release of caseinophosphopeptide (CPP)-rich fractions was studied and the physical properties of the fermented products determined. Trypsin treatment of skim milk led to increased fermentation times and a substantially lowered production of l -lactic acid as well as to delayed and reduced proteolysis caused by peptidases of the starter cultures. The functional properties of the milk proteins were decreased and the sensory properties less pronounced in yoghurt from trypsin-treated milk, but were described as less bitter than samples from nontreated milk. The CPP sequences β-CN(1–25)-4P and α s1 -CN(43–79)-7P were released during enzyme treatment.  相似文献   
93.
The objective of this study was to examine the effect of reducing sodium chloride (salt) on sensory and processing properties of chunked and formed ham. Chunked and formed hams were made with 0, .5, 1, 1.5 and 2% added salt. Results indicate that the 1.5% salt treatment possessed characteristics closely resembling the 2.0% salt treatment; however, the 1.5% salt treatment had slight reductions in yield, breaking force, and visual acceptability. Reduction of salt from 2.0% to 1.0% resulted in lower yield and sensory characteristics. Additional reductions in the level of salt below 1.0% further depressed yield and sensory characteristics.  相似文献   
94.
Field vines of cv. Sultana, grown either on their own roots, or grafted to a range of rootstocks, were drip‐irrigated at three salinity levels (0.40, 1.75 and 3.50 dS/m) over a five‐year period. Rootstocks comprised Ramsey, 1103 Paulsen, J17‐69 and 4 hybrids (designated R1, R2, R3 and R4) derived from parentage involving Vitis champini, V. berlandieri and V. vinifera. Concentrations of Cl, Na+, K+, Ca2+ and Mg2+ were measured in petioles at flowering, and in laminae and grape juice at harvest, in each year of the trial. Vines on all rootstocks accumulated less chloride in either petioles at flowering or in laminae and juice at harvest compared with vines on own roots at all salinity treatments. By inference, all rootstocks behaved as chloride excluders relative to the roots of own‐rooted vines. 1103 Paulsen was the best chloride excluder based on lowest concentrations of accumulated Cl in petioles, laminae and grape juice at high salinity. Sultana on R3 rootstock at high salinity accumulated more Na+ in both laminae and grape juice (at harvest) than did Sultana on own roots or on any of the other rootstocks. Laminae K+ at harvest time was reduced at high salinity in Sultana on own roots and on all rootstocks. Concentrations of both Cl and Na+ in petioles at flowering and in laminae and grape juice at harvest showed no significant correlation with either yield (as kg of fresh grapes per vine) or vigour (as measured by fresh weight of one‐year‐old pruning wood per vine) for any salinity treatment. There was however, a strong positive correlation between yield and the subsequent weight of one‐year‐old pruning wood for all salinity treatments. There was also a negative correlation between Na+ concentrations in petioles at flowering and the subsequent weight of one year‐old‐pruning wood from the 0.40 dS/m treatment. Similar negative correlations were found between Na+ concentration in both laminae and grape juice at harvest time, and the subsequent weight of one‐year‐old pruning wood from the 0.40 dS/m treatment (but not from either the 1.75 or 3.50 dS/m treatments). Based on these findings and those from Walker et al. 2002a we conclude that a high innate vigour of a rootstock combined with moderate to high chloride and sodium exclusion ability represents the best combination for salt tolerance in Sultana grapevines as measured by yield at moderate to high salinity.  相似文献   
95.
Toughening of whisker-reinforced (or fiber-reinforced) ceramics by whisker pullout requires debonding at the whisker/matrix interface. Compressive clamping stresses, which would inhibit interface debonding and/or pullout, are expected in composites where the matrix has a higher thermal expansion coefficient than the whisker. Because such mismatch in thermomechanical properties can result in brittle composites, it is important to explore approaches to modify the thermal stresses in composites. As a result, the effects of a film at the whisker/matrix interface on the stresses due to thermal contraction mismatch upon cooling are considered in this study. Analysis of various properties of the film are considered for the whisker/matrix systems, in particular for SiC/Al2O3, SiC/cordierite, and SiC/mullite composites. Reduction of thermomechanical stresses is shown to occur when the interfacial film has a low Young's modulus. Also, when the whisker has a lower thermal expansion coefficient than the matrix (e.g., SiC/Al2O3), the interfacial stresses generated during cooling decrease as the thermal expansion coefficient of the film increases.  相似文献   
96.
The sinterability of Al2O3/ZrO2 composite powder compacts containing 2 and 10 vol% ZrO2 was compared to the sinterability of their single-phase constituents through constant-heating-rate experiments. The ZrO2 inclusion phase delayed the initiation of bulk shrinkage and the temperature of maximum strain rate by 100°C. The ZrO2 inclusion phase also significantly inhibited grain growth. These results, discussed with regard to the thermodynamics of pore disappearance, suggest that phenomena inhibiting grain growth may also inhibit densification.  相似文献   
97.
The limits of miscibility within a portion of the system Na2O-ZnO-B2O3-SiO2 were determined at 650°, 800°, and 950°C. The miscibility gap at 800° and 950°C is a low dome, adjoining the zinc borosilicate miscibility gap. Below 755°C the dome intersects the Na2O-B2O3-SiO2 face of the phase diagram. The locus of this intersection is in agreement with literature data on the sodium borosilicate system. Estimated tie-line placement in the ZnO-B2O3-SiO2 miscibility gap at 1300°C resembles those reported for the corresponding CaO and SrO systems. The microscopic morphology of glasses with the weight composition xNa2O-18ZnO-18B2O3-64SiO2 with 0≤×≤12 is described in detail.  相似文献   
98.
A brief review of the reproductive system of the grapevine is presented. Phases discussed include floral induction and initiation during early spring, inflorescence primordium growth during summer to dormancy, flower formation at budburst in the subsequent growing season, and finally flowering and berry development. Difficulties in clearly defining and describing some of these developmental stages will be outlined, especially the complex bud system, the morphology of buds at budburst, and the course of flowering. The course of floral development during dormancy and at the time of budburst requires further attention, especially the reported effect that low temperature at budburst leads to increased numbers of flowers. Also, the recent finding that 'intercarpellar' floral organs can be induced by applying auxin is of particular interest and will be described. Case studies from Burgundy vineyards with Chardonnay, Pinot Noir and Gamay ovaries and berries will be included.
A detailed analysis of what constitutes a grape bunch will be presented from observations of Chardonnay inflorescences and bunches collected at random after set and at harvest in two seasons from spur-pruned, cane-pruned and hedged vines growing on two sites varying in climate and productivity (Adelaide Hills and Southern Vales of South Australia). This analysis covered variability in numbers of branches and flowers and in per cent berry set, as well as relationships between branch numbers and flower numbers. Relationships between flower numbers and per cent set, per cent set and berry size along the inflorescence, and berry size and seed complement are outlined. Likely implications of inter-bunch and intra-bunch variability for bunch compactness, berry composition and yield components are discussed.  相似文献   
99.
No Resistance     
In 2006, Peter Lynch (USA) and Gustavo Crembil (Argentina/USA) established THEM, an architectural partnership, after several years of a collaborative practice drawing upon the fields of design, architecture, performance art, communication, and social and ecological activism. The "Pleasure Garden," THEM's proposal for the 2008 YAP PS1/MoMA competition, continues an exploration of "craft in the age of globalization" and suggests what such an architecture might look like.  相似文献   
100.
A five parameter semi-empirical model is developed describing the apparent viscosity of a cooking dough as a function of applied shear rate, temperature, and time-temperature history. Such a model will be useful in the mathematical simulation of the extrusion cooking process. Other factors which can affect the apparent viscosity of a cooking dough are also discussed. The viscosity model is verified and the constants evaluated for a typical dough by combining the results of Amylograph and capillary viscometer experiments.  相似文献   
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