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31.
Wolfgang Müller 《中华纸业》2004,25(8)
介绍了Voith造纸技术控股股份有限公司近期研发的新技术和新装备,包括CompactPulper 损纸碎浆机,经过优化设计的回收浆车间废渣处理系统,适合于所有纸种脱水的靴式压榨技术--NipcoFlex和TissueFlex,PrintFlex P压榨毛布,VTT真空引纸系统,Duoshake摇振器,Strato系列橡胶包覆层新品种等. 相似文献
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Erica Perreca Franziska Eberl Maricel Valeria Santoro Louwrance Peter Wright Axel Schmidt Jonathan Gershenzon 《International journal of molecular sciences》2022,23(7)
White spruce (Picea glauca) emits monoterpenes that function as defensive signals and weapons after herbivore attack. We assessed the effects of drought and methyl jasmonate (MeJA) treatment, used as a proxy for herbivory, on monoterpenes and other isoprenoids in P. glauca. The emission of monoterpenes was significantly increased after MeJA treatment compared to the control, but drought suppressed the MeJA-induced increase. The composition of the emitted blend was altered strongly by stress, with drought increasing the proportion of oxygenated compounds and MeJA increasing the proportion of induced compounds such as linalool and (E)-β-ocimene. In contrast, no treatment had any significant effect on the levels of stored monoterpenes and diterpenes. Among other MEP pathway-derived isoprenoids, MeJA treatment decreased chlorophyll levels by 40%, but had no effect on carotenoids, while drought stress had no impact on either of these pigment classes. Of the three described spruce genes encoding 1-deoxy-D-xylulose-5-phosphate synthase (DXS) catalyzing the first step of the MEP pathway, the expression of only one, DXS2B, was affected by our treatments, being increased by MeJA and decreased by drought. These findings show the sensitivity of monoterpene emission to biotic and abiotic stress regimes, and the mediation of the response by DXS genes. 相似文献
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35.
Andreas Seifert Axel Berger Wolfgang Friedrich Müller 《Journal of the American Ceramic Society》1992,75(4):873-877
Sintered AIN specimens were deformed by Vickers hardness (HV) indentations. Compared with Al2 O3 the HV hardness values indicate a much higher plasticity of AIN at room temperature, but above 600°C a higher ductility for Al2 O3 . Deformed AIN specimens were examined by transmission electron microscopy. Basal and prismatic glide with the slip systems (0001) 〈1120〉 and {1 1 00}〈11 2 0〉 were frequently observed. This results in four linearly independent slip systems. The critical resolved shear stress for single prismatic slip seems to be even smaller than for basal slip. However, thermally activated dislocation reactions are frozen up to at least 1000°C. Thus, prismatic slip is suppressed as soon as more than one slip direction is activated. 相似文献
36.
In situ hydrogelation of injectable precursors upon biological stimulus is relevant to generate hydrogels under mild conditions and, potentially, at a biological side of interest. Here, it is shown that hydrolytic enzymes can be used to initiate the formation of covalent hydrogel networks, realizing a cleavage-leading-to-gelation strategy. For this purpose, a two-component system is used, consisting of a 4-arm polyethylene glycol-thiodepsipeptide conjugate, PEG4TDPo containing the matrix metalloproteinases MMP-2- and MMP-9-cleavable Ac-Pro-Leu-Gly#SLeu-Leu-Gly- thiodepsipeptide sequence releasing a thiol upon hydrolysis, and a maleimide functionalized 4-armed PEG (PEG4MAL). PEG4TDPo is synthesized in a PEG-functionalization protocol involving convergent and divergent synthetic steps without the need for rigorous purification procedures. In a fluorometric assay, it is shown that the construct is in fact cleaved by both investigated MMPs. PEG4TDPo in the presence of 10 wt.% PEG4MAL formed hydrogels upon addition of MMP-2 or -9 with average gelation times of 28 and 40 min, respectively, as is investigated by rheology. The much faster gelation times compared to the enzyme-free system showed the specific input of the enzymatic reactions. The MMP-assisted activation and crosslinking strategy can potentially become useful by targeting tissues showing an increased expression of MMPs, such as cancers, or to detect MMPs. 相似文献
37.
Jun.-Prof. Dr. Sabrina Hedrich Mareike Fritze Prof. Dr. Axel Schippers 《化学,工程师,技术》2023,95(12):1897-1908
Biohydrometallurgy as a section of hydrometallurgy uses specific metabolic capabilities of microorganisms for metal extraction. Biomining is the application of bioleaching for metal extraction from sulfide ores. For recycling, i.e., metal extraction from waste and industrial residues, there are no biohydrometallurgical technologies yet, but promising laboratory studies on metal extraction from solids. In this review article, these are summarized, and perspectives are shown. 相似文献
38.
A filtration system for keeping the analytics free of particles is usually required for inline characterization of particle‐laden process gasses. Additionally gas pumps may be needed for overcoming the pressure drop of filter element and filter cake. Consecutive reactions of process gas and filter cake may be disadvantageous for the quality of the gas analysis. A new probing apparatus is presented for extraction of particle‐free gas samples from particle‐laden process gasses. The probe combines the functionalities of a gas pump and a particle separator. While the gas is transported from process to analysis, particles are separated according to the principle of air classification. 相似文献
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40.
Genome-Wide Investigation of Multifocal and Unifocal Prostate Cancer—Are They Genetically Different?
Chinyere Ibeawuchi Hartmut Schmidt Reinhard Voss Ulf Titze Mahmoud Abbas Joerg Neumann Elke Eltze Agnes Marije Hoogland Guido Jenster Burkhard Brandt Axel Semjonow 《International journal of molecular sciences》2013,14(6):11816-11829
Prostate cancer is widely observed to be biologically heterogeneous. Its heterogeneity is manifested histologically as multifocal prostate cancer, which is observed more frequently than unifocal prostate cancer. The clinical and prognostic significance of either focal cancer type is not fully established. To investigate prostate cancer heterogeneity, the genetic profiles of multifocal and unifocal prostate cancers were compared. Here, we report observations deduced from tumor-tumor comparison of copy number alteration data of both focal categories. Forty-one fresh frozen prostate cancer foci from 14 multifocal prostate cancers and eight unifocal prostate cancers were subjected to copy number variation analysis with the Affymetrix SNP 6.0 microarray tool. With the investigated cases, tumors obtained from a single prostate exhibited different genetic profiles of variable degrees. Further comparison identified no distinct genetic pattern or signatures specific to multifocal or unifocal prostate cancer. Our findings suggest that samples obtained from multiple sites of a single unifocal prostate cancer show as much genetic heterogeneity and variability as separate tumors obtained from a single multifocal prostate cancer. 相似文献