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排序方式: 共有1259条查询结果,搜索用时 15 毫秒
1.
J Lorenz K Wilhelm M Kessler C Peschel U Schwulera R Lissner WG Struff E Huland C Huber WE Aulitzky 《Canadian Metallurgical Quarterly》1996,2(7):1115-1122
Safety, local and systemic immunomodulation, and tumor response to treatment with aerosolized natural interleukin 2 (nIL-2) applied five times a day were studied in a Phase I trial in 16 patients with pulmonary malignancies refractory to conventional therapy. The toxicity of inhaled nIL-2 was different from that observed after systemic administration. Reversible airway irritation causing a nonproductive cough represented the dose-limiting toxicity. Mild to moderate reduction of the vital capacity and forced expiratory volume (FEV1) with minor effects on relative FEV1, peak expiratory flow, airway resistance, and PaO2 was experienced by individual patients. In 14 patients suffering from pulmonary metastases due to renal cell cancer, one durable complete response, one partial response, and one mixed response were observed. Inhalation of nIL-2 aerosol resulted in a dose-dependent expansion of pulmonary immunocompetent cells in bronchoalveolar lavage fluid. Posttreatment bronchoalveolar lavage showed an activated lymphocyte phenotype with increased HLA-DR expression. The only systemic biological effect detectable in peripheral blood was a marked increase of soluble interleukin 2 receptor serum levels. We conclude that treatment with aerosolized nIL-2 is an effective means for site-specific immunomodulation and deserves further investigation for the treatment of malignant and inflammatory lung disease. 相似文献
2.
Klaus Lorenz 《化学,工程师,技术》1992,64(4):341-348
3.
A two-step replication process is described, allowing the non-destructive reproduction of micro-patterned tools. The first step comprises the embedding of the original part into silicone resin, the resin curing, and the separation of the part from the silicone rubber. The outstanding plasticity and the weak adherence of silicone rubber to most substrate materials facilitate retaining the original part. The second replication step, electroforming, requires silicone rubber metallization and contacting. The demonstrated technique is qualified mainly due to successful precautions against replication artifacts, related to silicone rubber deformability. 相似文献
4.
M. Hädrich N. Lorenz H. Metzner U. Reislöhner S. Mack M. Gossla W. Witthuhn 《Thin solid films》2007,515(15):5804-5807
In this paper, we describe our new baseline for CSS-CdTe-CdS solar cells on 10 × 10 cm2 substrates. The deposition of the p-n junction and all the following steps were performed at the Institut für Festkörperphysik (IFK) in Jena. Using the new baseline, we are already able to produce solar cells with similar properties as commercial ones. In the batch type process, all manufacturing steps can be investigated separately. We employ Rutherford backscattering spectrometry (RBS), X-ray diffraction (XRD) and external quantum efficiency (EQE) measurements to characterise the structure of the bulk materials and interfaces. It is demonstrated that by RBS the front contact becomes accessible for thinned CdTe films. At the back contact, RBS spectra show a tellurium accumulation which is due to etching. This tellurium rich layer is confirmed by XRD with Rietveld refinement. The intermixing at the CdS-CdTe interface caused by the activation step is quantified by a bandgap determination based on EQE measurements. From the bandgap energy of the CdTe1 − xSx compound, we calculated the sulphur fraction x at the interface. XRD measurements imply that the activation step induces a (111) texture in CdTe. With regard to an improved manufacturing process, our cells are compared to industrial cells produced by Antec Solar Energy. 相似文献
5.
The synthetic pyrethroids fenvalerate and cypermethrine, natural pyrethrum and lindane were investigated as wood preservatives under conditions of application to determine their contribution to indoor pollution. While pyrethrum degraded within 10 days, fenvalerate and cypermethrine showed high stability and long-term remaining in wood and no volatility into gasphase. In contrast to lindane they do not contribute to indoor pollution. 相似文献
6.
Cleyo Harris Travis O. Brenden Chris S. Vandergoot Matthew D. Faust Seth J. Herbst Charles C. Krueger 《Journal of Great Lakes research》2021,47(1):48-58
Infrequent captures of invasive, non-native grass carp (Ctenopharyngodon idella) have occurred in Lake Erie over the last 30+ years, with recent evidence suggesting wild reproduction in the lake’s western basin (WB) is occurring. Information on grass carp movements in the Laurentian Great Lakes is lacking, but an improved understanding of large-scale movements and potential areas of aggregation will help inform control strategies and risk assessment if grass carp spread to other parts of Lake Erie and other Great Lakes. Twenty-three grass carp captured in Lake Erie’s WB were implanted with acoustic transmitters and released. Movements were monitored with acoustic receivers deployed throughout Lake Erie and elsewhere in the Great Lakes. Grass carp dispersed up to 236 km, with approximately 25% of fish dispersing greater than 100 km from their release location. Mean daily movements ranged from <0.01 to 2.49 km/day, with the highest daily averages occurring in the spring and summer. The Sandusky, Detroit, and Maumee Rivers, and Plum Creek were the most heavily used WB tributaries. Seventeen percent of grass carp moved into Lake Erie’s central or eastern basins, although all fish eventually returned to the WB. One fish emigrated from Lake Erie through the Huron-Erie Corridor and into Lake Huron. Based on our results, past assessments may have underestimated the potential for grass carp to spread in the Great Lakes. We recommend focusing grass carp control efforts on Sandusky River and Plum Creek given their high use by tagged fish, and secondarily on Maumee and Detroit Rivers. 相似文献
7.
8.
Influence of compaction on the interfacial transition zone and the permeability of concrete 总被引:2,自引:0,他引:2
Andreas Leemann Beat Münch Philippe Gasser Lorenz Holzer 《Cement and Concrete Research》2006,36(8):1425-1433
The interfacial transition zone (ITZ) is regarded as a key feature for the transport properties and the durability of concrete. In this study one self-compacting concrete (SCC) mixture and two conventionally vibrated concrete (CVC) mixtures are studied in order to determine the influence of compaction on the porosity of the ITZ. Additionally oxygen permeability and water conductivity were measured in vertical and horizontal direction. The quantitative analysis of images made with an optical microscope and an environmental scanning electron microscope shows a significantly increased porosity and width of the ITZ in CVC compared to SCC. At the same time oxygen permeability and water conductivity of CVC are increased in comparison to SCC. Moreover, considerable differences in the porosity of the lower, lateral and upper ITZ are observed in both types of concrete. The anisotropic distribution of pores in the ITZ does not necessarily cause anisotropy in oxygen permeability and water conductivity though. 相似文献
9.
The underpotential deposition (UPD) of Cd on “real” and “quasi-ideal” silver single crystal surfaces of (111) and (100) crystallographic orientation as well as on polycrystalline silver substrate has been investigated in 0.5 M Na2SO4 supporting electrolyte solutions. At high underpotentials 100 < ΔE < 350 mV, the UPD is characterized by a quasi-reversible adsorption/desorption of Cd whereas at low underpotentials. ΔE < 50 mV, an increase of the anodic stripping charge with the polarization time is found due to the formation of an AgCd alloy at the substrate surface. The time dependence of this process can be described by a parabolic rate law, the rate constant of which is a function of ΔE and temperature T. Relatively low activation energies of about 70 kJmol?1 were determined from measurements at 293 ? T ? 338 K. The results are discussed in terms of a semi-infinite-linear diffusion model. The alloy formation process is assumed to be initiated by a place exchange between Ag substrate atoms and vacancy sites within a mobile Cd adsorbate layer thus forming the initial stage of a highly distorted AgCd alloy. The further growth will take place by the movement of Ag atoms through the vacancy-rich surface alloy and the simultaneous deposition of Cd at the interface AgCd/Cd2+. 相似文献
10.
Aqueous dispersions of anionic polyurethanes were prepared by reaction of polyethers, 1,6-hexamethylene diisocyanate, 1,2,4-benzenetricarboxylic acid anhydride and triethyl amine. Formation of the dispersion was achieved by phase reversal or by precipitation. Phase reversal occurred when the solution or the melt of the polymer was treated with water, while precipitation took place when the solution was stirred into water. The amount of acetone used has an effect on the mean particle diameter, D?T, obtained by turbidity measurements. There was an optimal acetone concentration at which D?T reached a minimum. A similar effect was observed when tetrahydrofuran, 2-butanone or acetonitrile were used as solvents instead of acetone. When the dispersion was formed by precipitation, only adequately diluted acetonic solutions formed colloidal dispersions, while concentrated solutions gave dispersions with a broad particle size distribution. 相似文献