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101.
A ${\text{Pd/}}\gamma {\text{ - Al}}_{\text{2}} {\text{O}}_{\text{3}}$ membrane supported on a macroporous $\alpha {\text{ - Al}}_{\text{2}} {\text{O}}_{\text{3}}$ tube was prepared by sol–gel processing and used in the partial hydrogenation of acetylene and 1,3-butadiene. The average pore diameter of the ${\text{Pd/}}\gamma {\text{ - Al}}_{\text{2}} {\text{O}}_{\text{3}}$ membrane was 3.6 nm. The gases were separated by Knudsen diffusion. The activity and selectivity of the ${\text{Pd/}}\gamma {\text{ - Al}}_{\text{2}} {\text{O}}_{\text{3}}$ membrane was compared to that of ${\text{Pd/}}\gamma {\text{ - Al}}_{\text{2}} {\text{O}}_{\text{3}}$ catalysts used in a conventional packed bed reactor. The highest selectivity to the partially hydrogenated products occurred when the reactant was premixed with H2 and was passed through the membrane wall.  相似文献   
102.
Extracellular vesicles (EVs) are membranous, rounded vesicles released by prokaryotic and eukaryotic cells in their normal and pathophysiological states. These vesicles form a network of intercellular communication as they can transfer cell- and function-specific information (lipids, proteins and nucleic acids) to different cells and thus alter their function. Fungi are not an exception; they also release EVs to the extracellular space. The vesicles can also be retained in the periplasm as periplasmic vesicles (PVs) and the cell wall. Such fungal vesicles play various specific roles in the lives of these organisms. They are involved in creating wall architecture and maintaining its integrity, supporting cell isolation and defence against the environment. In the case of pathogenic strains, they might take part in the interactions with the host and affect the infection outcomes. The economic importance of fungi in manufacturing high-quality nutritional and pharmaceutical products and in remediation is considerable. The analysis of fungal EVs opens new horizons for diagnosing fungal infections and developing vaccines against mycoses and novel applications of nanotherapy and sensors in industrial processes.  相似文献   
103.
Characterization of the pollution charge of drainages from pyrite mines of Aljustrel (Portugal) was made. Laboratory experiments were performed in order to recover copper by cementation and remove iron, zinc and acidity by neutralization with lime. It was found that the removal of the metal ions is completed when pH reaches a step at 5.0–5.5, whichever the ratio between Fe(II) and Fe(III).  相似文献   
104.
The technical and financial performance of high yield Eucalyptus biomass in a co-current dilute acid pretreatment followed by enzymatic hydrolysis process was simulated using WinGEMS® and Excel®. Average ethanol yield per dry Mg of Eucalyptus biomass was approximately 347.6 L of ethanol (with average carbohydrate content in the biomass around 66.1%) at a cost of $0.49 L−1 of ethanol, cash cost of ∼ $0.46 L−1 and CAPEX of $1.03 L−1 of ethanol. The main cost drivers are: biomass, enzyme, tax, fuel (gasoline), depreciation and labor. Profitability of the process is very sensitive to biomass cost, carbohydrate content (%) in biomass and enzyme cost. Biomass delivered cost was simulated and financially evaluated in Part I; here in Part II the conversion of this raw material into cellulosic ethanol using the dilute acid process is evaluated.  相似文献   
105.
The genetic variants of κ-casein (κ-CN) A and B were analysed in milk from Holstein–Friesian (HF) and Jersey cows by means of isoelectric focusing (IEF) electrophoresis. Milk samples were obtained in triplicate from pure-breed HF and Jersey cows (three of each) to estimate the protein content, casein and purify κ-CN. The protein and casein contents in the milk from both breeds were statistically different ( P <  0.05). The κ-CN A migrates first with an isoelectric point (pI) of 7.2–7.3 and then B with a pI of 7.5–7.7. Differences in the expression proportion of both variants were detected.  相似文献   
106.
上罗拉皮圈是复杂的纺线生产流程中一个很小的细节。然而,由于它们对成纱质量有较大影响,必须对它们进行优先考虑。质量不是一个简单的问题,它包括多个方面(橡胶质量、正确的加工、定期的保养)。因此,皮圈的选择就像保养操作的自动化程度一样影响成本产生。本文将就这个问题进行讨论。  相似文献   
107.
A submersible microbial fuel cell (SMFC) was utilized to treat sewage sludge and simultaneously generate electricity. Stable power generation (145 +/- 5 mW/m2, 470 omega) was produced continuously from raw sewage sludge for 5.5 days. The maximum power density reached 190 +/- 5 mW/m2. The corresponding total chemical oxygen demand (TCOD) removal efficiency was 78.1 +/- 0.2% with initial TCOD of 49.7 g/L. The power generation of SMFC was depended on the sludge concentration, while dilution of the raw sludge resulted in higher power density. The maximum power density was saturated at sludge concentration of 17 g-TCOD/L, where 290 mw/m2 was achieved. When effluents from an anaerobic digester that was fed with raw sludge were used as substrate in the SMFC, a maximum power density of 318 mW/m2, and a final TCOD removal of 71.9 +/- 0.2% were achieved. These results have practical implications for development of an effective system to treat sewage sludge and simultaneously recover energy.  相似文献   
108.
109.
Based on our comprehensive theoretical investigation and known experimental results for small boron clusters, we predict the existence of a novel aromatic inorganic molecule, B12H6. This molecule, which we refer to as borozene, has remarkably similar properties to the well-known benzene. Borozene is planar, possesses a large first excitation energy, D 3h symmetry, and more importantly is aromatic. Furthermore, the calculated anisotropy of the magnetic susceptibility of borozene is three times larger in absolute value than for benzene. Finally, we show that borozene molecules may be fused together to give larger aromatic compounds with even larger anisotropic susceptibilities.  相似文献   
110.
Platelet-activating factor (PAF) is a potent autacoid that participates in inflammation and other pathophysiological processes. In this review we deal with recent evidence suggesting that PAF is a mediator that is released early during glomerular injury. PAF can be synthesized in the glomerulus by infiltrating intrinsic glomerular cells. Normal glomeruli produce PAF upon stimulation, and glomerular PAF synthesis is increased in a variety of experimental glomerulopathies. The local infusion of PAF into the renal artery of isolated blood-free kidneys induces proteinuria. PAF attracts and activates inflammatory cells. Glomerular mesangial, endothelial and epithelial cells are also targets for PAF. Therapy with specific PAF receptor antagonists has prevented or reduced proteinuria and improved glomerular inflammation in several experimental models of proliferative glomerulonephritis and minimal change nephrosis. However, the beneficial effect of administration of PAF antagonists once proteinuria is fully developed has been minimal. PAF may also play a role in the recruitment of inflammatory interstitial cells. Based on a paper presented at the Third International Conference on Platet-Activating Factor and Structurally Related Alkyl Ether Lipids, Tokyo, Japan, May 1989.  相似文献   
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