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101.
By studying letters written to the dead published in the popular Israeli press between 1997 and 2014, this paper examines the practices that constitute communicative acts toward a deceased person using interpersonal and mass media, in order to embody the recipiency of the dead. Using an analytical framework that draws on media ecology, communication theory, and discourse analysis, the paper demonstrates how the epistolary and mass media rhetoric operate to reconstruct the performance of the dead as an addressee. By exploring this understudied phenomenon and revisiting core notions of communication in light of written technologies, distance, and death, the paper argues that this communicative constellation, as a whole, is a performative act that offers a “communicative resurrection” to the dead.  相似文献   
102.
Ionic liquids (ILs) are attractive (co‐)solvents for biocatalysis. However, in high concentration (>10 % IL), enzymes usually show decreased activity. No general principles have been discovered to improve IL resistance of enzymes by protein engineering. We present a systematic study to elucidate general engineering principles by site saturation mutagenesis on the complete gene bsla. Screening in presence of four [BMIM]‐based ILs revealed two unexpected lessons on directed evolution: 1) resistance improvement was obtainable at 50–69 % of all amino acid positions, thus explaining the success of small sized random mutant libraries; 2) 6–13 % of substitutions led to improved resistance. Among these, 66–95 % were substitutions by chemically different amino acids (e.g., aromatic to polar/aliphatic/charged amino acids), thus indicating that mutagenesis methods introducing such changes should, at least for lipases like BSLA, be favored to improve IL resistance.  相似文献   
103.
104.
An improved immobilised Grubbs 2nd generation catalyst and its application in flow‐through devices, shown for on‐column reaction gas chromatography (ocRGC), has been studied. The coupling of a reaction capillary and a separation column in GC/MS allows direct reaction monitoring and analysis of conversion as well as reaction kinetics. The presented permanently bonded N‐heterocyclic carbene ligand shows a great stability and activity in ring closing metathesis reactions. A salt‐free approach was used to generate the carbene ligand, which can be directly monitored by mass spectrometry. The very flexible design of the immobilised ligand system in reaction channels and capillaries of flow through systems allows the preparation of various catalysts using a broad variety of metal precursors. This strategy of immobilised catalytically active complexes offers a wide range of on‐column reactions combinable with fast reaction screening by high throughput experimentation.

  相似文献   

105.
The objective of this work is to establish nominal friction stir [butt] welding process parameters for joining 4.76-mm-thick aluminum alloys 6061-T6 and 7075-T6 and to improve the joint quality via programmed tool offsets. In addition, dynamic tool–workpiece interface temperatures are measured during welding and used to explain the effects of alloy placement and weld tool offset from the joint. Weld tool offsets into the retreating side AA7075 increase the measured tensile strength of the dissimilar joint. The increased joint strength is facilitated by lower average weld temperatures with increasing amount of AA7075 stirred into the nugget.  相似文献   
106.
Four multiparous, ruminally and duodenally cannulated Holstein cows in midlactation were utilized in a 4 x 4 Latin square to evaluate the effects of supplemental fat from sources varying in proportions of unsaturated and saturated fatty acids on nutrient digestion and lactation performance. All diets (45% alfalfa hay) contained 12% whole cottonseed (as-fed); treatments were no supplemental fat (control, 3% total fatty acids, dry matter basis) or additional 2% tallow, 2% yellow grease, or 2% blend (60% tallow: 40% yellow grease). The unsaturated to saturated fatty acid ratios were 1:1 for tallow and 2.5:1 for yellow grease. Dry matter intake, apparent ruminal and total tract digestibilities of organic matter, neutral detergent fiber, acid detergent fiber, N, and fatty acids, and microbial efficiency were similar across treatments. Microbial N flow to the duodenum was increased by yellow grease. Supplemental fat reduced the postruminal digestibility of fatty acids, primarily the saturated fatty acids; increasing saturation of the fat source magnified the reduction. Total volatile fatty acid concentrations and ruminal fluid pH were unaffected by fat supplementation or saturation level. Blend decreased ruminal pH and acetate to propionate ratio. Yields of milk and milk fat increased with fat supplementation. Concentrations and yields of trans vaccenic acid in milk increased linearly with the unsaturated fatty acid content of the fat supplement. Modest supplementation using highly unsaturated fats to diets containing whole cottonseed can increase milk production without disturbing rumen function, evident by the similar VFA concentrations, nutrient digestibilities, and milk composition.  相似文献   
107.
Aerosol emissions from international shipping are recognized to have a large impact on the Earth's radiation budget, directly by scattering and absorbing solar radiation and indirectly by altering cloud properties. New regulations have recently been approved by the International Maritime Organization (IMO) aiming at progressive reductions of the maximum sulfur content allowed in marine fuels from current 4.5% by mass down to 0.5% in 2020, with more restrictive limits already applied in some coastal regions. In this context, we use a global bottom-up algorithm to calculate geographically resolved emission inventories of gaseous (NO(x), CO, SO(2)) and aerosol (black carbon, organic matter, sulfate) species for different kinds of low-sulfur fuels in shipping. We apply these inventories to study the resulting changes in radiative forcing, attributed to particles from shipping, with the global aerosol-climate model EMAC-MADE. The emission factors for the different fuels are based on measurements at a test bed of a large diesel engine. We consider both fossil fuel (marine gas oil) and biofuels (palm and soy bean oil) as a substitute for heavy fuel oil in the current (2006) fleet and compare their climate impact to that resulting from heavy fuel oil use. Our simulations suggest that ship-induced surface level concentrations of sulfate aerosol are strongly reduced, up to about 40-60% in the high-traffic regions. This clearly has positive consequences for pollution reduction in the vicinity of major harbors. Additionally, such reductions in the aerosol loading lead to a decrease of a factor of 3-4 in the indirect global aerosol effect induced by emissions from international shipping.  相似文献   
108.
The rate and extent of estimated energy mobilization and the relationship between fat depth at the rib and thurl and body condition score (BCS) were investigated in Jersey and Holstein cows in early lactation. Twenty-six cows were paired by breed, parity, and calving date, and were individually fed a total mixed ration ad libitum from parturition through 120 d in milk. Feed intake and milk production were measured daily; body weight (BW), BCS, subcutaneous fat depth, milk composition, and concentration of plasma nonesterified fatty acids were measured every 2 wk. Estimated tissue energy balance (TEB) was calculated using 1989 NRC equations. Net energy intake was greater in early lactation for Holsteins compared with Jerseys, 37.8 and 28.2 Mcal/d, respectively. Milk energy was greater for Holsteins relative to Jerseys, 30.5 versus 21.2 Mcal/d. Fat depth and BCS did not differ between breeds. A positive relationship existed between fat depth and BCS for Jerseys; however, there was no significant relationship for Holsteins. The best-fit regression model for predicting TEB for Holsteins and Jerseys in early lactation included week of lactation, milk composition, and BCS. Jerseys remained in negative TEB for a shorter period of time relative to Holsteins. The TEB nadir was -6.19 and -12.9 Mcal/d, for Jerseys and Holsteins, respectively. Expressed as a proportion of metabolic BW (BW(0.75)), net energy intake did not differ between breeds, yet milk energy and estimated tissue energy loss were greater for Holsteins compared with Jerseys.  相似文献   
109.
Deposition of Cu(In,Ga)Se2 (CIGS) thin film solar cells on metallic substrate is an attractive approach for development of low cost solar modules. However, in such devices, special care has to be taken to avoid diffusion of impurities, such as Fe, Ni, and Cr, from the substrate into the active layers. In this work, the influence of Ni and Cr impurities on the electronic properties of CIGS thin film solar cells is investigated in detail. Impurities were introduced into the CIGS layer by diffusion during the CIGS deposition process from a Ni or Cr precursor layer below the Mo electrical back contact. A high temperature and a low temperature CIGS deposition process were applied in order to correlate the changes in the photovoltaic parameters with the amount of impurities diffused into the absorber layer. Solar cells with Ni and Cr impurities show a reduction in the device performance, whereas the effect was most pronounced in Ni containing devices. The presence of deep defect levels in the absorber layer was identified with admittance spectroscopy and can be related to Ni and Cr impurities, which diffused into the CIGS layer according to secondary ion mass spectroscopy depth profiles and inductively coupled plasma mass spectrometry. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
110.
The role of conference proceedings for scientific communication varies among the different research fields. It is thus difficult to determine how to use them in bibliometric studies that cover all or at least a variety of the research fields without favouring or penalizing observation subjects that are specialized in fields that rely heavily on conference proceedings. Also, the coverage of conference proceedings in bibliometric databases is often unclear. Not only have there been reports of misclassification but also of insufficient coverage. In this study, the Web of Science is used to give an overview of coverage of conference proceedings as well as advantages and pitfalls of their usage in bibliometric analyses. In particular, the focus lies on different citation behaviour of and for conference proceedings and the implications for bibliometric indicators. This is complemented by an investigation of the development of coverage and publication behaviour in conference proceedings which is compared to those of journal publications. Finally, the importance but also drawbacks and opportunities of acknowledging conference proceedings publications for bibliometric studies are summarized.  相似文献   
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