A. Messerer  H.‐J. Schmid  C. Knab  U. Pschl  R. Nießner 《化学，工程师，技术》2004,76(8):1092-1096

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Frank-Gerrit Klrner  Ulrike Kalthof  Joachim Gante 《Advanced Synthesis u0026amp; Catalysis》1997,339(1):359-364

From the pressure-induced rate enhancement the activation volume of the peptide coupling 1 with the sodium salt of glycine 2 leading to the corresponding dipeptide derivative 3 was determined to be strongly negative (ΔV^≠ = −(19.3 ± 0.5) cm³mol⁻¹ at 51.7 °C, CH₃OH). This finding indicates that and association with the developing of charge proceeds in the rate-determining transition state. The pressure-induced peptide coupling was exploited to synthesize a derivative ( 12a, b ) of glutathione (γ-Glu-Cys-Gly), a biologically important tripeptide, starting from either glycine or glutamic acid.  相似文献   

    

Joachim Molkentin  Dietz Precht 《European Journal of Lipid Science and Technology》2000,102(3):194-201

Gas‐chromatographic analysis of butyric acid (C4) in mixed spreadable fats can be used to calculate the milk fat proportion, either by additional analysis of the underlying pure milk fat (component sample) or by using a mean C4 content instead. After comparison of several analytical variants and subsequent development of an improved draft standard for quantitation of milk fat in mixed fats, this draft was checked for accuracy in three EU‐wide ring tests performed with 26 participating laboratories. Due to the natural variation of the butyric acid content in European milk fats, deviations from the actual milk fat content may amount up to ± 10% in addition to analytical errors when calculating with a mean C4 content instead of the C4 content of a component sample. Though the reproducibility could be improved by application of correction factors derived from a reference fat, only the calculation based on the additional analysis of a component sample of the pure milk fat led to an acceptable accuracy concerning the trueness of the results in combination with good repeatability (r) and reproducibility (R). Finally, several further improvements of the draft standard led to a precision of r = 4.3% and R = 6.0% relative to the mean of two milk fat contents determined. Thus, the tested procedure proved its suitability for a control method of the declared milk fat content in mixed fat spreads.  相似文献   

    

Yi Zhou  Wangqiao Chen  Jixin Zhu  Wenbo Pei  Chengyuan Wang  Ling Huang  Cheng Yao  Qinyu Yan  Wei Huang  Joachim Say Chye Loo  Qichun Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(23):4874-4885

Hydrogen sulfide (H₂S) is an important gaseous signaling agent mediated by many physiological processes and diseases. In order to explore its role in biological signaling, much effort has been focused on developing organic fluorescent probes to image H₂S. However, these downconversion H₂S probes are impractical for bio‐imaging beyond a certain depth because of the short tissue penetration of UV/visible light (as an excitation source). In most circumstance, these probes are also not suitable for long‐term assay due to photo‐bleaching. Herein, a new design to detect H₂S based on the coumarin‐hemicyanine (CHC1)‐modified upconversion nanophosphors is reported. This inorganic–organic integrated nanoprobe is demonstrated to display a fast response time with a large ratiometric upconversion luminescence (UCL) enhancement, and extraordinary photo‐stability. CHC1‐UCNPs not only can be used for ratiometric UCL monitoring of pseudo‐enzymatic H₂S production in living cells, but can also be used to identify the risk of endotoxic shock through ratiometric UCL imaging of tissue and measurement of endogenous H₂S levels in plasma. The first ratiometric UCL H₂S nanoprobe reported here may be further developed as the next‐generation diagnostic tool for the detection of inflammatory‐related diseases.  相似文献   

    

Nikolay L. Vaklev  Robert Müller  Beinn V. O. Muir  David T. James  Roger Pretot  Paul van der Schaaf  Jan Genoe  Ji‐Seon Kim  Joachim H. G. Steinke  Alasdair J. Campbell 《Advanced Materials Interfaces》2014,1(3)

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Judith Guasch  Bert Conings  Stefanie Neubauer  Florian Rechenmacher  Karen Ende  Claudio G. Rolli  Christian Kappel  Viktoria Schaufler  Alexandre Micoulet  Horst Kessler  Hans‐Gerd Boyen  Elisabetta Ada Cavalcanti‐Adam  Joachim P. Spatz 《Advanced materials (Deerfield Beach, Fla.)》2015,27(25):3737-3747

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Man‐Rong Li  Mark Croft  Peter W. Stephens  Meng Ye  David Vanderbilt  Maria Retuerto  Zheng Deng  Christoph P. Grams  Joachim Hemberger  Joke Hadermann  Wen‐Min Li  Chang‐Qing Jin  Felix O. Saouma  Joon I. Jang  Hirofumi Akamatsu  Venkatraman Gopalan  David Walker  Martha Greenblatt 《Advanced materials (Deerfield Beach, Fla.)》2015,27(13):2177-2181

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Dr. Hans‐Joachim Riechers 《Mauerwerk》2015,19(5):403-406

The work of plastering and rendering masonry and concrete is covered by a huge range of standards and guidelines. The new publication “Guidelines for plastering and rendering masonry and concrete” presents a standard work, which clarifies the issues for designers and contractors alike.  相似文献   

    

B. Bttger  J. Eiken  M. Ohno  G. Klaus  M. Fehlbier  R. Schmid‐Fetzer  I. Steinbach  A. Bührig‐Polaczek 《Advanced Engineering Materials》2006,8(4)

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Pan Y  Neuss S  Leifert A  Fischler M  Wen F  Simon U  Schmid G  Brandau W  Jahnen-Dechent W 《Small (Weinheim an der Bergstrasse, Germany)》2007,3(11):1941-1949

Gold nanoparticles are widely used in biomedical imaging and diagnostic tests. Based on their established use in the laboratory and the chemical stability of Au(0), gold nanoparticles were expected to be safe. The recent literature, however, contains conflicting data regarding the cytotoxicity of gold nanoparticles. Against this background a systematic study of water-soluble gold nanoparticles stabilized by triphenylphosphine derivatives ranging in size from 0.8 to 15 nm is made. The cytotoxicity of these particles in four cell lines representing major functional cell types with barrier and phagocyte function are tested. Connective tissue fibroblasts, epithelial cells, macrophages, and melanoma cells prove most sensitive to gold particles 1.4 nm in size, which results in IC(50) values ranging from 30 to 56 microM depending on the particular 1.4-nm Au compound-cell line combination. In contrast, gold particles 15 nm in size and Tauredon (gold thiomalate) are nontoxic at up to 60-fold and 100-fold higher concentrations, respectively. The cellular response is size dependent, in that 1.4-nm particles cause predominantly rapid cell death by necrosis within 12 h while closely related particles 1.2 nm in diameter effect predominantly programmed cell death by apoptosis.  相似文献