Comparison of the sulfation rates of calcium,magnesium and zinc oxides with SO2 and SO3

The sulfation rates of reagent grade calcium and zinc oxides and technical grade magnesium oxide with sulfur trioxide and sulfur dioxide - oxygen mixtures have been measured thermogravimetrically. Experiments have been conducted to determine the rate of reaction for various particle radii (0.071-0.151 mm), temperatures (450-1100 K.) and concentrations of sulfur dioxide, sulfur trioxide (0.075-0.62 moles/m³), oxygen (0-1.5 moles/m³). Experimental results are presented which compare the sulfation rates of each basic oxide with sulfur dioxide and sulfur trioxide at different temperatures. The rate of sulfation of different oxides are compared under the same experimental conditions.     

Henry's law constant for hydrogen in high temperature water with dissolved lithium and boron

The results of measurement of the Henry's law constant are reported for solutions of H₂ in H₂O, with dissolved lithium and boron, at high temperature (220 to ～300°C). The experimental procedure involved the use of a palladium/hydrogen electrical resistance sensor to determine the hydrogen gas pressure in equilibrium with the hydrogen dissolved in the water. Values of for the above solutions were lower than values for the solute‐free H₂/H₂O solutions. For conditions typical of a Pressurized Water Reactor (PWR) the lowering amounted to about 3%.     

Reactivation of partially-sulphated limestone particles from a cfb combustor by hydration

Spent limestone samples from the bed and baghouse of a 22 MWe circulating fluidized bed (CFB) boiler were hydrated and then sulphated in a thermogravimetric analyzer under conditions similar to those found in CFB combustors (850°C, 0.3% SO₂, 9% O₂, 9% CO₂ and 81.7% N₂). Hydration using water gave faster rates and higher levels of conversion of the residual CaO to Ca (OH)₂ than immersion in pure steam at 150 and 200°C. The particles expanded during hydration and their internal volume increased from 0.1 cm³/g Ca before hydration to nearly 0.6 cm³/g Ca after dehydration. Hydration rejuvenated the reactivity of the bed material but not that of the baghouse particles. The conversion of Ca to CaSO₄, in the treated bed particles increased from 32% to over 80% during re-sulphation.     

Exergy analysis of a chemical metallurgical process

The concept of available work or exergy is used to develop an expression from which the causes of exergy losses in a chemical reactor are identified. The concept is illustrated by application to a lead blast furnace. The performance of the sinter plant and the lead smelter are assessed by the same procedures. The possibilities of exergy recovery are discussed and a heat pump installation is described. The advantages of the exergy method of process assessment relative to the traditional heat balance are discussed.     

CTL responses induced by a single immunization with peptide encapsulated in biodegradable microparticles

A synthetic peptide representing a measles virus (MV) cytotoxic T cell epitope (CTL) when encapsulated in poly (D,L-lactide co-glycolide) (PLG) 50:50 microparticles induced a strong CTL response after a single intraperitoneal immunization of mice which was greater than that following administration of the peptide in Freund's complete adjuvant. A 100 micrograms dose of encapsulated peptide was shown to be more effective for CTL priming than 50 and 25 micrograms doses. A vaccine formulation prepared by simply mixing empty 50:50 PLG microparticles with the peptide resulted in the induction of CTL responses comparable to those induced by the encapsulated peptide. Moreover, a CTL response against MV-infected target cells was observed. These findings highlight the potential immunostimulatory effect of PLG microparticles for the induction of MV and peptide-specific CTL responses.     

The role of adjuvant chemotherapy in the treatment of adult soft tissue sarcomas

The influence of the postantibiotic effects (PAEs) of ciprofloxacin, pefloxacin, imipenem, meropenem and amikacin in the suprainhibitory concentrations (2 x and 4 x MIC) on the metabolic processes of P. aeruginosa was studied. The synthesis of macromolecules was expressed by influencing of the incorporation rate of [14C] adenine and [14C] leucine. Remarkable affecting of both biosynthetic processes evoked the suprainhibitory concentration 4 x MIC of meropenem by inhibition of the nucleic acids synthesis to 76.1% and proteins synthesis to 61.1% against the control. The suprainhibitory concentration 4 x MIC of both pefloxacin and ciprofloxacin affected the highest suppression of the endogenous respiration to 16.5% and to 20.3%, respectively. The respiration was influenced the least after the effect of meropenem in the both suprainhibitory concentrations tested. According to our knowledge, this is first report about the evaluation of the endogenous respiration after PAE. In this study we demonstrated the inhibitory effects of 4 x MIC concentration of antibiotics studied on the metabolic processes of P. aeruginosa. The results suggest a multiple mechanism for the PAE.     

A flat surface robotic gripper for handling limp material

A prototype flat-surface, single-chambered and multi-chambered gripper, based on the operational principle of suction and pressure differential has been designed, implemented and experimentally tested. The prototype grippers are proven sufficient to pick and place fabric material accurately and reliably without causing any distortion and/or folding of the fabric. Both prototype grippers have been mounted on AdeptOne and AdeptThree robot arms for experimental and reliability analysis. They both meet requirements as set by the US apparel industry, related to pick and place single cut plies of several types of fabric     

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因特网技术使网上书店亚马逊(amazon.com)可以在实际库存极少的情况下,将尽可能多的书目集中起来,为顾客提供最丰富的选择,并以网上签单提供最快捷的购货方式.这种方式使亚马逊甩掉了图书中间商,把出版社与顾客直接联系起来,很快超过老牌的传统书店,取得了巨大成功,并因此成为网上销售的典范,各行各业的商家群起效仿.但"亚马逊模式"是一种普遍适用的妙方吗?<财富>杂志(Fortune)刊登的这篇文章以一位投资家的眼光,提出了不同意见.     

Clinical and in vitro effects of recombinant human erythropoietin in patients receiving intensive chemotherapy for small-cell lung cancer

PURPOSE: Recombinant human erythropoietin (r-Hu-EPO) is known to be effective in untreated cancer patients. Here we assess the possibility that r-Hu-EPO may also prevent or reduce anemia in patients who receive cytotoxic chemotherapy. METHODS: Thirty-six patients with small-cell lung carcinoma (SCLC) were enrolled onto a three-arm, randomized trial to investigate the effect of r-Hu-EPO on hemoglobin (Hb) levels and RBC and platelet (Plt) transfusions during chemotherapy. Bone marrow progenitors were studied before and after treatment. Two groups of patients received r-Hu-EPO at a dose of either 150 IU/kg (group 150) or 300 IU/kg (group 300) three times per week for the duration of chemotherapy. A control group did not receive r-Hu-EPO (group O). A maximum of six cycles of a chemotherapy regimen that consisted of vincristine, ifosfamide, carboplatin, and etoposide (VICE) were given to all patients. Hematologic parameters were measured weekly, and RBC or Plt transfusions were given for Hb levels less than 9 g/dL and Plt counts less than 20 x 10(9)/L. RESULTS: Hb levels decreased in all patients, but onset of anemia was delayed in groups that received r-Hu-EPO (P = .002). A total of 116 U RBC were transfused in group 0, 54 in group 150, and 52 in group 300 (P = .017). In addition, there was a nonsignificant trend toward higher Plt counts and fewer Plt transfusions in patients who received r-Hu-EPO. CONCLUSION: r-Hu-EPO at a dose of either 150 or 300 IU/kg three times weekly delays the onset of anemia and reduces RBC transfusion requirements in patients who undergo intensive chemotherapy for SCLC. A possible effect of r-Hu-EPO on platelet numbers deserves further study.