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Theoretical and practical considerations in electrostatic depositioning of charged polymers 下载免费PDF全文
An interfacial engineering technology, based on the electrostatic deposition of charged polyelectrolytes onto surfaces of oppositely charged templates is reviewed with an emphasis on practical applications in the food, pharmaceutical and personal care industries. On interfaces of disperse systems consecutively deposited polymers provide major advantages in terms of physical and chemical stability of dispersions against superimposed stresses (pH, temperature, ionic strength, freezing, chilling, dehydration, lipid oxidation). The controlled deposition of multiple layers allows for a controlled and triggered release of incorporated functional components. This review highlights the basic principles of the layer‐by‐layer (LbL) electrostatic deposition method as well as some major advantages and drawbacks of this approach. An overview of several systems that can be used as templates for the deposition including emulsion droplets, liposomal vehicles, colloidal aggregates, and planar surfaces is given. Suitable substrates for the deposition are presented with a focus on charged biopolymers such as proteins or polysaccharides since they play an essential role in the formulation and stabilization of food, pharmaceutical and personal care applications. Issues and difficulties associated with implementing the technology on a larger, industrial scale are discussed. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40099. 相似文献
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Efficient Engineering and Production Concepts for Products in Regulated Environments – Dream or Nightmare? 下载免费PDF全文
Prof. Jochen Strube Dr. Reinhard Ditz Holger Fröhlich Dr. Dirk Köster Dr. Thomas Grützner Dr. Jörg Koch Dr. Rüdiger Schütte 《化学,工程师,技术》2014,86(5):687-694
Manufacturing of chemical‐pharmaceutical products is moving increasingly fast on a global scale. Therefore, developing and starting up production facilities fast, with high quality, and at reasonable costs has become extremely challenging. Engineering concepts like modularization, standardization and simultaneous/parallel engineering are discussed as methods for speeding up process design and filing for regulatory approval. Transfer from batch to continuous operation mode of production is pointed out as the key‐issue in such strategies. 相似文献
75.
H. Schick H.-P. Welzel S. Schwarz G. Truckenbrodt 《Advanced Synthesis \u0026amp; Catalysis》1985,327(1):91-95
A convenient method to convert homoallyl or homopropargyl ketones or alcohols into 4-oxo carboxylic acids or γ-lactones is the oxidative cleavage of the multiple bond with potassium permanganate in diluted sulfuric acid. This is exemplified by the preparation of intermediates for the synthesis of 8-methylprostaglandin C2. The oxidation of the allylic compounds with permanganate is compared with the oxidative cleavage by ozone/hydrogen peroxide, ozone/chromic acid or sodium periodate/potassium permanganate. 相似文献
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Acute myeloid leukemia (AML) is the most common acute leukemia in adults. The standard of care in medically and physically fit patients is intensive induction therapy. The majority of these intensively treated patients achieve a complete remission. However, a high number of these patients will experience relapse. In patients older than 60 years, the results are even worse. Therefore, new therapeutic approaches are desperately needed. One promising approach in high-risk leukemia to prevent relapse is the induction of the immune system simultaneously or after reduction of the initial tumor burden. Different immunotherapeutic approaches such as allogenic stem cell transplantation or donor lymphocyte infusions are already standard therapies, but other options for AML treatment are in the pipeline. Moreover, the therapeutic landscape in AML is rapidly changing, and in the last years, a number of immunogenic targets structures eligible for specific therapy, risk assessment or evaluation of disease course were determined. For example, leukemia-associated antigens (LAA) showed to be critical as biomarkers of disease state and survival, as well as markers of minimal residual disease (MRD). Yet many mechanisms and properties are still insufficiently understood, which also represents a great potential for this form of therapy. Therefore, targeted therapy as immunotherapy could turn into an efficient tool to clear residual disease, improve the outcome of AML patients and reduce the relapse risk. In this review, established but also emerging immunotherapeutic approaches for AML patients will be discussed. 相似文献
77.
Jochen Aβfalg 《国际自动化与计算杂志》2007,4(2):141-148
This paper presents an internal model approach for modeling and diagnostic functionality design for nonlinear systems operating subject to single- and multiple-faults. We therefore provide the framework of structured augmented state models. Fault characteristics are considered to be generated by dynamical exosystems that are switched via equality constraints to overcome the augmented state observability limiting the number of diagnosable faults. Based on the proposed model, the fault diagnosis problem is specified as an optimal hybrid augmented state estimation problem. Sub-optimal solutions are motivated and exemplified for the fault diagnosis of the well-known three-tank benchmark. As the considered class of fault diagnosis problems is large, the suggested approach is not only of theoretical interest but also of high practical relevance. 相似文献
78.
H. Schick H.-P. Welzel S. Schwarz G. Truckenbrodt 《Advanced Synthesis \u0026amp; Catalysis》1982,324(4):550-556
Prostaglandins and Prostaglandin Intermediates. Oxidative Cleavage of Olefins by Ozonization and Oxidation in the Solvent System Acetone/tert. Butanol – a Method for Preparation of Substituted Cyclopentyl Acetic Acids Oxidative cleavage of olefinic double bonds by ozonization in acetone in the presence of tert. butanol followed by oxidation with JONES ' reagent in the same solvent system gives carboxylic acids and/or ketones in good yields. Acetic acid or water can be used instead of tert. butanol with the same success. This “one-pot” procedure was developed in connection with the synthesis of intermediates for the preparation of 8-methyl-prostaglandin C2. 相似文献
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Hans-Joachim Nees Harald Keller Thomas Facklam Albert Herrmann Jochen Welsch Uwe Bergstrßer Heinrich Heydt Manfred Regitz 《Advanced Synthesis \u0026amp; Catalysis》1993,335(7):589-598
Diazo Compounds. 72. Diazoalkylphosphanes – Synthesis by Electrophilic Diazoalkane Substitution and Oxidative Addition Reactions at Phosphorus Electrophilic diazoalkane substitution of the diazomethyl compounds 1a,b with the chloro phosphanes 2a-o in the presence of lithium diethylamide yields the diazoalkyl phosphanes 3a-z . Oxidative addition of oxygen, sulfur and selenium at phosphorus leads into the series of oxo, thioxo and selenoxo phosphanes having diazoalkyl substituents ( 4a-d, 5a-m and 7a-d ). The silyl group of 5n,o is cleaved by chromatography on aluminium oxide to yield the (diazomethyl)phosphane sulfides 6a,b . 相似文献