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1.
In the chemical industry large amounts of saline wastewater occur. Its disposal into rivers is a considerable burden to the ecosystem. To strive for a circular economy and enable a viable raw material recycling, energy-efficient concentration processes are requisite. High-pressure reverse osmosis meets this criterion, but its industrial application demands suitable membrane elements that withstand the exceptional operation conditions and provide sufficient performance. Hence, new requirements regarding the design of spiral-wound elements arise. To identify those, specific performance-limiting effects need a better understanding. 相似文献
2.
Gerd J. Hahn 《国际生产研究杂志》2020,58(5):1425-1441
The Fourth Industrial Revolution – also known as Industry 4.0 (i4.0) – comprises the digitalisation of the industrial sector. This paper uses the theoretical lens of supply chain innovation (SCI) to investigate the implications of i4.0 on supply chain management. For these purposes, the method of structured content analysis is applied to more than 200 use cases of i4.0-enabled SCI introduced by both established and startup companies. i4.0-enabled SCI manifests along three dimensions: process, technology, and business architecture. The key findings of this study can be summarised as follows: first, i4.0-enabled SCI extends the initial focus on productivity improvements in SC processes towards scalability and flexibility. Second, extant i4.0 solutions rely mostly on analytics and smart things while omitting smart people technology and the human-centric approach associated with the i4.0 paradigm. Third, established companies adopt i4.0 merely to sustain their existing business architectures while startup companies radically change their operating models, relying heavily on data analytics and the platform economy. Consequently, established companies pursue a problem-driven, engineering-based approach to SCI while startup companies follow an ‘asset-light’, business-driven approach. Lastly, there are two distinct approaches to digitalising operational SC processes: platform-based crowdsourcing of standard processes and on-demand provision of customised services. 相似文献
3.
Dr. Tomasz Ratajczyk Prof. Dr. Gerd Buntkowsky Dr. Torsten Gutmann Dr. Bartłomiej Fedorczyk Dr. Adam Mames Dr. Mariusz Pietrzak Zuzanna Puzio Piotr Grzegorz Szkudlarek 《Chembiochem : a European journal of chemical biology》2021,22(5):855-860
The biorelevant PyFALGEA oligopeptide ligand, which is selective towards the epidermal growth factor receptor (EGFR), has been successfully employed as a substrate in magnetic resonance signal amplification by reversible exchange (SABRE) experiments. It is demonstrated that PyFALGEA and the iridium catalyst IMes form a PyFALGEA:IMes molecular complex. The interaction between PyFALGEA:IMes and H2 results in a ternary SABRE complex. Selective 1D EXSY experiments reveal that this complex is labile, which is an essential condition for successful hyperpolarization by SABRE. Polarization transfer from parahydrogen to PyFALGEA is observed leading to significant enhancement of the 1H NMR signals of PyFALGEA. Different iridium catalysts and peptides are inspected to discuss the influence of their molecular structures on the efficiency of hyperpolarization. It is observed that PyFALGEA oligopeptide hyperpolarization is more efficient when an iridium catalyst with a sterically less demanding NHC ligand system such as IMesBn is employed. Experiments with shorter analogues of PyFALGEA, that is, PyLGEA and PyEA, show that the bulky phenylalanine from the PyFALGEA oligopeptide causes steric hindrance in the SABRE complex, which hampers hyperpolarization with IMes. Finally, a single-scan 1H NMR SABRE experiment of PyFALGEA with IMesBn revealed a unique pattern of NMR lines in the hydride region, which can be treated as a fingerprint of this important oligopeptide. 相似文献
4.
The increased use of carbon fiber reinforced thermosets generates more waste and end-of-life products. However, an efficient recycling method for the expensive carbon fibers has not yet been developed. The selective decomposition of amine-cured epoxy resin under mild conditions is presented. A two-step method was investigated to decompose the epoxy resin. The optimum parameters were initially determined using a model compound. By analysis of the reaction products, a cleavage of the C–N bond according to the Cope elimination could be proven. Therefore, the Cope elimination is suggested as the main step of the decomposition of amine-cured epoxy resins in presence of hydrogen peroxide. By dissolving the resin, it is possible to recover resin-free fibers with unimpaired mechanical properties. 相似文献
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7.
Anticancer Potential of (Pentamethylcyclopentadienyl)chloridoiridium(III) Complexes Bearing κP and κP,κS‐Coordinated Ph2PCH2CH2CH2S(O)xPh (x=0–2) Ligands 下载免费PDF全文
Gerd Ludwig Ivan Ranđelović Dr. Danijela Maksimović‐Ivanić Dr. Sanja Mijatović Mirna Z. Bulatović Dr. Djordje Miljković Prof. Marcus Korb Prof. Dr. Heinrich Lang Prof. Dr. Dirk Steinborn Prof. Dr. Goran N. Kaluđerović 《ChemMedChem》2014,9(7):1586-1593
Iridium(III) complexes of the type [Ir(η5‐C5Me5)Cl2{Ph2PCH2CH2CH2S(O)xPh‐κP}] (x=0–2; 1 – 3 ) and [Ir(η5‐C5Me5)Cl{Ph2PCH2CH2CH2S(O)xPh‐κP,κS}][PF6] (x=0–1; 4 and 5 ) with 3‐(diphenylphosphino)propyl phenyl sulfide, sulfoxide, and sulfone ligands Ph2PCH2CH2CH2S(O)xPh were designed, synthesized, and characterized fully, including X‐ray diffraction analyses for complexes 3 and 4 . In vitro studies against human thyroid carcinoma (8505C), submandibular carcinoma (A253), breast adenocarcinoma (MCF‐7), colon adenocarcinoma (SW480), and melanoma (518A2) cell lines provided evidence for the high biological potential of the neutral and cationic iridium(III) complexes. Neutral iridium(III) complex 5 proved to be the most active, with IC50 values up to about 0.1 μM , representing activities of up to one order of magnitude higher than cisplatin. Using 8505C cells, apoptosis was shown to be the main mechanism through which complex 5 exerts its tumoricidal action. The described iridium(III) complexes represent potential leads in the search for novel metal‐based anticancer agents. 相似文献
8.
Dr. Carolyn Vargas Prof. Dr. Gerald Radziwill Dr. Gerd Krause Dr. Anne Diehl Prof. Dr. Sandro Keller Dr. Nestor Kamdem Prof. Dr. Constantin Czekelius Annika Kreuchwig Dr. Peter Schmieder Dr. Declan Doyle Prof. Dr. Karin Moelling Dr. Volker Hagen Dr. Markus Schade Prof. Dr. Hartmut Oschkinat 《ChemMedChem》2014,9(7):1458-1462
PDZ (PSD‐95, Dlg, ZO‐1) domains are ubiquitous interaction modules that are involved in many cellular signal transduction pathways. Interference with PDZ‐mediated protein–protein interactions has important implications in disease‐related signaling processes. For this reason, PDZ domains have gained attention as potential targets for inhibitor design and, in the long run, drug development. Herein we report the development of small molecules to probe the function of the PDZ domain from human AF6 (ALL1‐fused gene from chromosome 6), which is an essential component of cell–cell junctions. These compounds bind to AF6 PDZ with substantially higher affinity than the peptide (Ile‐Gln‐Ser‐Val‐Glu‐Val) derived from its natural ligand, EphB2. In intact cells, the compounds inhibit the AF6–Bcr interaction and interfere with epidermal growth factor (EGF)‐dependent signaling. 相似文献
9.
Barregard L Horvat M Mazzolai B Sällsten G Gibicar D Fajon V Dibona S Munthe J Wängberg I Haeger Eugensson M 《The Science of the total environment》2006,368(1):326-334
As part of the European Mercury Emissions from Chlor Alkali Plants (EMECAP) project, we tested the hypothesis that contamination of ambient air with mercury around chlor alkali plants using mercury cells would increase the internal dose of mercury in people living close to the plants. Mercury in urine (U-Hg) was determined in 225 individuals living near a Swedish or an Italian chlor alkali plant, and in 256 age- and sex-matched individuals from two reference areas. Other factors possibly affecting mercury exposure were examined. Emissions and concentrations of total gaseous mercury (TGM) around the plants were measured and modeled. No increase in U-Hg could be demonstrated in the populations living close to the plants. This was the case also when the comparison was restricted to subjects with no dental amalgam and low fish consumption. The emissions of mercury to air doubled the background level, but contributed only about 2 ng/m(3) to long-term averages in the residential areas. The median U-Hg levels in subjects with dental amalgam were 1.2 microg/g creatinine (micro/gC) in Italy and 0.6 microg/gC in Sweden. In individuals without dental amalgam, the medians were 0.9 microg/gC and 0.2 microg/gC, respectively. The number of amalgam fillings, as well as chewing, fish consumption, and female sex were associated with higher U-Hg. The difference between the countries is probably due to higher fish consumption in Italy, demethylated methyl mercury (MeHg) being partly excreted in urine. Post hoc power calculations showed that if the background mercury exposure is low it may be possible to demonstrate an increase in U-Hg of as little as about 10 ng/m(3) as a contribution to ambient mercury from a point source. 相似文献
10.
Gerd Lüttig 《Bulletin of Engineering Geology and the Environment》1986,33(1):27-30
Contrary to public opinion, gravel and sand are mineral raw materials that are not available in unlimited quantities, and, at any place. In quantity and economic value they belong to the top-ranking resources on a world scale. Supplies are not unlimited: lifetime is very short in some regions. Being very vulnerable to changes in transport costs and sensitive with respect to conflicts between environmental protection and mining, sand and gravel require scientific effort in order that new deposits be found and the lifetime of reserves increased. 相似文献