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751.
The Application of Microemulsions as a Washing-System in the Finishing Industry In the textile finishing in many areas dispers systems are been used or develop during the processing. Examples are the dyeing bath for polyester fibers in which hydrophobic dyestuff acts as an dispersion in water. Another example for such a system occurs during washing. In such a case the oil-surfactant-water system changes from a solution of surfactant in water into oil-in-water emulsion as a function of dwelling-time. The present paper discusses the usefulness of a one phase water-oil-surfactant system in textile finishing processes. In detail a physico-chemical characterisation of a many component system consisting of water/hydrophob/amphiphil (surfactant)/electroyte is been needed. The behaviour of such systems is dependent on the chemical structure of the components and of pressure and temperature. Those systems show one-, two- and threephase regions. In this paper evidence will be given that the conditions having the highest degree of efficiency toward cleanness of the textile goods occurs in the one-phase region close to the three phase transition. 相似文献
752.
Oksana Suraeva Anke Kaltbeitzel Katharina Landfester Frederik R. Wurm Ingo Lieberwirth 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(25):2206454
Typically, 2D nanosheets have a homogeneous surface, making them a major challenge to structure. This study proposes a novel concept of 2D organic nanosheets with a heterogeneously functionalized surface. This work achieves this by consecutively crystallizing two precisely synthesized polymers with different functional groups in the polymer backbone in a two-step process. First, the core platelet is formed and then the second polymer is crystallized around it. As a result, the central area of the platelets has a different surface functionality than the periphery. This concept offers two advantages: the resulting polymeric 2D platelets are stable in dispersion, which simplifies further processing and makes both crystal surfaces accessible for subsequent functionalization. Additionally, a wide variety of polymers can be used, making the process and the choice of surface functionalization very flexible. 相似文献
753.
Virtual Reality - Nowadays, digitalization has an immense impact on the landscape of jobs. This technological revolution creates new industries and professions, promises greater efficiency and... 相似文献
754.
755.
Metal Ion Promiscuity and Structure of 2,3-Dihydroxybenzoic Acid Decarboxylase of Aspergillus oryzae
Dr. Gerhard Hofer Dr. Xiang Sheng Dr. Simone Braeuer Dr. Stefan E. Payer Dr. Katharina Plasch Prof. Dr. Walter Goessler Prof. Dr. Kurt Faber Prof. Dr. Walter Keller Prof. Dr. Fahmi Himo Dr. Silvia M. Glueck 《Chembiochem : a European journal of chemical biology》2021,22(4):652-656
Broad substrate tolerance and excellent regioselectivity, as well as independence from sensitive cofactors have established benzoic acid decarboxylases from microbial sources as efficient biocatalysts. Robustness under process conditions makes them particularly attractive for preparative-scale applications. The divalent metal-dependent enzymes are capable of catalyzing the reversible non-oxidative (de)carboxylation of a variety of electron-rich (hetero)aromatic substrates analogously to the chemical Kolbe-Schmitt reaction. Elemental mass spectrometry supported by crystal structure elucidation and quantum chemical calculations verified the presence of a catalytically relevant Mg2+ complexed in the active site of 2,3-dihydroxybenoic acid decarboxylase from Aspergillus oryzae (2,3-DHBD_Ao). This unique example with respect to the nature of the metal is in contrast to mechanistically related decarboxylases, which generally have Zn2+ or Mn2+ as the catalytically active metal. 相似文献
756.
757.
Magdalena Staniszewska Pedro Fragoso Costa Matthias Eiber Jasmin M. Klose Jasmin Wosniack Henning Reis Tibor Szarvas Boris Hadaschik Katharina Lückerath Ken Herrmann Wolfgang P. Fendler Janette Iking 《International journal of molecular sciences》2021,22(14)
Prostate-specific membrane antigen (PSMA)-directed radioligand therapy (RLT) prolongs overall survival in men with metastatic castration-resistant prostate cancer (mCRPC). However, men with low PSMA expression are excluded from RLT. We explored the effect of androgen receptor blockade with enzalutamide on PSMA expression. Assessment of PSMA and androgen receptor (AR) expression on the human PC cell lines 22Rv1, C4-2, and LNCaP by immunohistochemistry and flow cytometry revealed low (22Rv1) and high (C4-2 and LNCaP) PSMA expression, and high, comparable AR positivity. Treatment with enzalutamide increased PSMA levels in 22Rv1, C4-2, and LNCaP (2.2/2.3/2.6-fold, p = 0.0005/0.03/0.046) after one week compared to DMSO-treated controls as assessed by flow cytometry. NOD/Scid mice bearing 22Rv1 tumors were treated with enzalutamide for two weeks. Positron emission tomography/computed tomography (PET/CT) demonstrated higher tumor uptake of 68Ga-PSMA after enzalutamide treatment (p = 0.004). Similarly, a clinical case with low baseline PSMA avidity demonstrated increased uptake of 68Ga-PSMA after enzalutamide on PET/CT and post-therapeutic 177Lu-PSMA scintigraphy in a patient with mCRPC. Enzalutamide induced PSMA expression in the 22Rv1 xenograft model and in an mCRPC patient, both with low baseline tumoral PSMA levels. Therefore, enzalutamide pre-treatment might render patients with low PSMA expression eligible for 177Lu-PSMA RLT. 相似文献
758.
Weber M Faerber P Meyer V Lott C Eickert G Fabricius KE De Beer D 《Environmental science & technology》2007,41(17):6210-6215
Microsensors are powerful tools for microenvironment studies, however their use has often been restricted to laboratory applications due to the lack of adequate equipment for in situ deployments. Here we report on new features, construction details, and examples of applications of an improved diver-operated motorized microsensor profiler for underwater field operation to a water depth of 25 m. The new motorized profiler has a final precision of 5 microm, and can accommodate amperometric Clark-type microsensors for oxygen and hydrogen sulfide, potentiometric microsensors (e.g., for pH, Ca2+), and fiber-optic irradiance microsensors. The profiler is interfaced by a logger with a signal display, and has pushbuttons for underwater operation. The system can be pre-programmed to autonomous operation or interactively operated by divers. Internal batteries supply power for up to 24 h of measurements and 36 h of data storage (max. 64 million data points). Two flexible stands were developed for deployment on uneven or fragile surfaces, such as coral reefs. Three experimental pilot studies are presented, where (1) the oxygen distribution in a sand ripple was 3-D-mapped, (2) the microenvironment of sediment accumulated on a stony coral was studied, and (3) oxygen dynamics during an experimental sedimentation were investigated. This system allows SCUBA divers to perform a wide array of in situ measurements, with deployment precision and duration similar to those possible in the laboratory. 相似文献
759.
Muñoz-Espí R Dolcet P Rossow T Wagner M Landfester K Crespy D 《ACS applied materials & interfaces》2011,3(11):4292-4298
Tin dioxide coatings are widely applied in glasses and ceramics to improve not only optical, but also mechanical properties. In this work, we report a new method to prepare SnO(2) coatings from aqueous dispersions of polymer/organotin hybrid nanoparticles. Various liquid organotin compounds were encapsulated in polymeric nanoparticles synthesized by miniemulsion polymerization. Large amounts of tetrabutyltin and bis(tributyltin) could be successfully incorporated in cross-linked and noncross-linked polystyrene nanoparticles that served as sacrificial templates for the formation of tin oxide coatings after etching with oxygen plasma or calcination. Cross-linked polystyrene particles containing bis(tributyltin)--selected for having a high boiling point--were found to be especially suited for the oxide coating formation. The content of metal in the particles was up to 12 wt %, and estimations by thermogravimetrical indicated that at least 96% of the total organotin compound was converted to SnO(2). The resulting coatings were mainly identified as tetragonal SnO(2) (cassiterite) by X-ray diffraction, although a coexistence of this phase with orthorhombic SnO(2) was observed for samples prepared with bis(tributyltin). 相似文献
760.
C Grabosch K Kolbe TK Lindhorst 《Chembiochem : a European journal of chemical biology》2012,13(13):1874-1879
Glycoarrays-easier than ever: Glycoarrays were fabricated on polystyrene microtiter plates with great ease by using a tandem process that combined hydrophobic adsorption and thiourea bridging. They were validated by testing specific bacterial adhesion and its inhibition. 相似文献