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To study the dietetic effect of canned natural Ivasi herring, containing up to 10% of eicosopentenic acid, the blood serum was analyzed in 37 patients with coronary heart disease at Vladivostok City Hospital and in 73 patients at the Regional Cardiological Sanatorium. Lipid characteristics of the blood serum (total cholesterol, alpha- and beta-cholesterol, beta-lipoproteins) were comparatively studied in 5 groups of subjects: normal subjects, two control groups (who did not receive the dietetic product) and two groups who received Ivasi herring. A favourable effect on all above parameters was recorded in more than 50% of patients in the sanatorium. The frequency of favourable shifts was higher in patients who received Ivasi herring than in the controls, the highest changes concerned beta-cholesterol. No significant improvement was recorded in coronary patients during the acute period (the group at the City Hospital). The results of the investigation have evidenced the expediency of using canned Ivasi herring in the diet therapy and prevention of coronary heart disease during the rehabilitation period. 相似文献
23.
Philip Dobie Julie Dendy Christine Sherman Jenny Padgham Anna Wood Angharad M. R. Gatehouse 《Journal of Stored Products Research》1990,26(4):177-186
The importance of carefully applied bioassay techniques is highlighted for identifying resistance of Phaseolus spp to the bruchids Acanthoscelides obtectus (Say) and Zabrotes subfasciatus Boheman. Two potential sources of resistance are identified amongst the varieties of P. vulgaris screened. In one the presence of a lectin-like protein (LLP) was identified, which has previously been associated with resistance, while in the other, resistance may be linked to the presence of a novel protein, similar to but not the same as LLP. The use of anti-LLP antibodies are suggested as a useful tool for distinguishing between resistant and susceptible varieties. Five varieties of P. lunatus and six of P. acutifolius are shown to be resistant to A. obtectus, and the potential is recognized for transferring resistant genes to P. vulgaris via interspecific crosses. 相似文献
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Monomolecular and Bimolecular Recombination of Electron–Hole Pairs at the Interface of a Bilayer Organic Solar Cell 下载免费PDF全文
Tobias Hahn Steffen Tscheuschner Frank‐Julian Kahle Markus Reichenberger Stavros Athanasopoulos Christina Saller Guillermo C. Bazan Thuc‐Quyen Nguyen Peter Strohriegl Heinz Bässler Anna Köhler 《Advanced functional materials》2017,27(1)
While it has been argued that field‐dependent geminate pair recombination (GR) is important, this process is often disregarded when analyzing the recombination kinetics in bulk heterojunction organic solar cells (OSCs). To differentiate between the contributions of GR and nongeminate recombination (NGR) the authors study bilayer OSCs using either a PCDTBT‐type polymer layer with a thickness from 14 to 66 nm or a 60 nm thick p‐DTS(FBTTh2)2 layer as donor material and C60 as acceptor. The authors measure JV‐characteristics as a function of intensity and charge‐extraction‐by‐linearly‐increasing‐voltage‐type hole mobilities. The experiments have been complemented by Monte Carlo simulations. The authors find that fill factor (FF) decreases with increasing donor layer thickness (Lp) even at the lowest light intensities where geminate recombination dominates. The authors interpret this in terms of thickness dependent back diffusion of holes toward their siblings at the donor–acceptor interface that are already beyond the Langevin capture sphere rather than to charge accumulation at the donor–acceptor interface. This effect is absent in the p‐DTS(FBTTh2)2 diode in which the hole mobility is by two orders of magnitude higher. At higher light intensities, NGR occurs as evidenced by the evolution of s‐shape of the JV‐curves and the concomitant additional decrease of the FF with increasing layer thickness. 相似文献
25.
Functionalized Graphene as Extracellular Matrix Mimics: Toward Well‐Defined 2D Nanomaterials for Multivalent Virus Interactions 下载免费PDF全文
Mohammad Fardin Gholami Daniel Lauster Kai Ludwig Julian Storm Benjamin Ziem Nikolai Severin Christoph Böttcher Jürgen P. Rabe Andreas Herrmann Mohsen Adeli Rainer Haag 《Advanced functional materials》2017,27(15)
Polysulfated nanomaterials that mimic the extracellular cell matrix are of great interest for their potential to modulate cellular responses and to bind and neutralize pathogens. However, control over the density of active functional groups on such biomimetics is essential for efficient interactions, and this remains a challenge. In this regard, producing polysulfated graphene derivatives with control over their functionality is an intriguing accomplishment in order to obtain highly effective 2D platforms for pathogen interactions. Here, a facile and efficient method for the controlled attachment of a heparin sulfate mimic on the surface of graphene is reported. Dichlorotriazine groups are conjugated to the surface of graphene by a one‐pot [2+1] nitrene cycloaddition reaction at ambient conditions, providing derivatives with defined functionality. Consecutive step by step conjugation of hyperbranched polyglycerol to the dichlorotriazine groups and eventual conversion to the polyglycerol sulfate result in the graphene based heparin biomimetics. Scanning force microscopy, cryo‐transmission electron microscopy, and in vitro bioassays reveal strong interactions between the functionalized graphene (thoroughly covered by a sulfated polymer) and vesicular stomatitis virus. Infection experiments with highly sulfated versions of graphene drastically promote the infection process, leading to higher viral titers compared to nonsulfated analogues. 相似文献
26.
Kierstin Torres Agnieszka Kuc Lorenzo Maschio Thang Pham Kate Reidy Lukas Dekanovsky Zdenek Sofer Frances M. Ross Julian Klein 《Advanced functional materials》2023,33(12):2211366
Understanding the stability limitations and defect formation mechanisms in 2D magnets is essential for their utilization in spintronic and memory technologies. Here, defects in mono- to multilayer CrSBr are correlated with structural, vibrational, and magnetic properties. Resonant Raman scattering is used to reveal distinct vibrational defect signatures. In pristine CrSBr, it is shown that bromine atoms mediate vibrational interlayer coupling, allowing for distinguishing between surface and bulk defect modes. Environmental exposure is shown to cause drastic degradation in monolayers, with the formation of intralayer defects. This is in contrast to multilayers that predominantly show bromine surface defects. Through deliberate ion irradiation, the formation of defect modes is tuned: these are strongly polarized and resonantly enhanced, reflecting the quasi--1D electronic character of CrSBr. Strikingly, pronounced signatures of spin-phonon coupling of the intrinsic phonon modes and the ion beam-induced defect modes are observed throughout the magnetic transition temperature. Overall, defect engineering of magnetic properties is possible, with resonant Raman spectroscopy serving as a direct fingerprint of magnetic phases and defects in CrSBr. 相似文献
27.
Len Sherman 《电子设计技术》2004,11(3):168-170
便携式设备,如PDA、智能电话和数码相机等在使用电池供电时具有特殊的电源管理要求,效率指标固然重要,而来自尺寸和价格方面的压力也要通过不同的设计加以平衡,这些实际要求都不同于笔记本电脑等电池供电设备的设计.除了对尺寸和重量的限制外,手持产品还需解决散热问题.这些产品中不可能安装风扇,也不可能容忍较高的温度,如果这些问题得不到解决,对元件尺寸的苛刻要求很难使其达到适当的效率,同时,小型电池需要严格的电源管理,上述因素都是当电源集成在系统内部时所要考虑的. 相似文献
28.
29.
由近距离低温面目标热成像系统的信号方程和噪声等效温差NETD的定义,导出了NETDoc1/M,并由此得到MRTDoc1/M,MDTDoc1/M,从而证明了热成像系统的温差分辨率;NETD、MRTD、MDTD均要求微发光谱匹配因数M要大,这为选用光谱区配因数M和M作为热成像系统的综合评价参数奠定了理论基础。 相似文献
30.
Christina Gretener Julian Perrenoud Lukas Kranz Luisa Kneer Rafael Schmitt Stephan Buecheler Ayodhya N. Tiwari 《Progress in Photovoltaics: Research and Applications》2013,21(8):1580-1586
The ability to grow efficient CdTe/CdS solar cells in substrate configuration would not only allow for the use of non‐transparent and flexible substrates but also enable a better control of junction formation. Yet, the problems of barrier formation at the back contact as well as the formation of a p–n junction with reduced recombination losses have to be solved. In this work, CdTe/CdS solar cells in substrate configuration were developed, and the results on different combinations of back contact materials are presented. The Cu content in the electrical back contact was found to be a crucial parameter for the optimal CdCl2‐treatment procedure. For Cu‐free cells, two activation treatments were applied, whereas Cu‐containing cells were only treated once after the CdTe deposition. A recrystallization behavior of the CdTe layer upon its activation similar to superstrate configuration was found; however, no CdTe–CdS intermixing could be observed when the layers were treated consecutively. Remarkably high VOC and fill factor of 768 mV and 68.6%, respectively, were achieved using a combination of MoO3, Te, and Cu as back contact buffer layer resulting in 11.3% conversion efficiency. With a Cu‐free MoO3/Te buffer material, a VOC of 733 mV, a fill factor of 62.3%, and an efficiency of 10.0% were obtained. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献