Whey protein concentrates and isolates: Processing and functional properties

Substantial progress has been made in understanding the basic chemical and structural properties of the principal whey proteins, that is, β‐lactoglobulin β‐Lg), α‐lactalbumin (α‐La), bovine serum albumin (BSA), and immunoglobulin (Ig). This knowledge has been acquired in terms of: (1) procedures for isolation, purification, and characterization of the individual whey proteins in buffer solutions; and (2) whey fractionation technologies for manufacturing whey protein concentrates (WPC) with improved chemical and functional properties in food systems. This article is a critical review of selected publications related to (1) whey fractionation technology for manufacturing WPC and WPI; (2) fundamental properties of whey proteins; and (3) factors that affect protein functionality, that is, composition, protein structure, and processing.     

Effects of Halogenation of Small-Molecule and Polymeric Acceptors for Efficient Organic Solar Cells

Tuning the properties of non-fullerene acceptors (NFAs) through halogenation, including fluorination and chlorination, represents one of the most promising strategies to boost the performance of organic solar cells (OSCs). However, it remains unclear how the F and Cl choice influences the molecular packing and performance between small-molecule and polymeric acceptors. Here, a series of small-molecule and polymeric acceptors with different amounts and types of halogenation is synthesized, and the effects of fluorination and chlorination between small-molecule and polymeric acceptors are investigated. It is found that chlorinated small-molecule acceptors lead to longer exciton diffusion length and better performance compared to the corresponding fluorinated ones, which attributes to their stronger intermolecular packing mode. For polymer acceptors, in contrast, the fluorinated polymers achieve a denser packing mode and better performance, because chlorinated polymers exhibit reduced intrachain conjugation between end group moieties and linker units. This study demonstrates different halogenation effects on the packing modes and performances for small-molecule and polymeric acceptors, which provides important guidance for the molecule design of high-performance acceptors for OSCs.     

Er~+注入单晶硅中非晶层晶化过程的TEM研究

剖面透射电镜的变温观察及高分辨电子显微镜(HREM)象表明,Er~+注入(注入能量350kev,注入剂量1×10~(15)cm~(-2))硅单晶后,在表面可形成一连续非晶层。热退火过程中,非晶层可以从非晶/单晶界面处进行固相外延和在内部成核两种方式进行再结晶以至形成多晶层。再结晶的晶粒中存在大量微孪晶和堆垛层错。     

On the capacity of Rayleigh fading cooperative systems under adaptive transmission

In this letter, the use of adaptive source transmission with amplify-and-forward relaying is proposed. Three different adaptive techniques are considered: (i) optimal simultaneous power and rate adaptation; (ii) constant power with optimal rate adaptation; (iii) channel inversion with fixed rate. The capacity upper bounds of these adaptive protocols are derived for the amplify-and-forward cooperative system over both independent and identically distributed (i.i.d.) Rayleigh fading and non-i.i.d. Rayleigh fading environments. The capacity analysis is based on an upper bound on the effective received signal-to-noise ratio (SNR). The tightness of the upper bound is validated by the use of a lower bound and by Monte Carlo simulation. It is shown that at high SNR the optimal simultaneous power and rate adaptation and the optimal rate adaptation with constant power provide roughly the same capacity. Channel inversion is shown to suffer from a deterioration in capacity relative to the other adaptive techniques.     

流体静压力下应变闪锌矿(111)取向GaN/AlGaN量子阱中受屏蔽激子的结合能

结合变分法与自洽计算方法研究了流体静压力下应变闪锌矿(111)取向GaN/AlχGa1-χN量子阱中受电子-空穴气体屏蔽的激子结合能.计算中,考虑了沿(111)取向生长多层结构时存在压电极化引起的内建电场.计算结果表明,考虑压力对双轴及单轴应变的调制以及禁带宽度、有效质量和介电常数等参数的压力效应时,激子结合能随压力的增大近似线性增加;且当电子-空穴气体密度大时,这一效应更加显著.当给定压力时,随着电子.空穴气面密度的增加,激子结合能先缓慢增加,但当密度达到大约1011cm-2时结合能开始迅速衰减.此外,当减小垒的厚度时,由于内建电场减弱,激子结合能显著增加.     

GB 17743-2007与GB 17743-1999差异解析

文章详细介绍了GB17743标准新旧版本在内容上的差异,并对新版标准的理解提出自己的见解。     

Buckling Instability Control of 1D Nanowire Networks for a Large‐Area Stretchable and Transparent Electrode

A commonly used strategy to impose deformability on conductive materials is the prestrain method, in which conductive materials are placed on prestretched elastic substrates and relaxed to create wavy or wrinkled structures. However, 1D metallic nanowire (NW) networks typically result in out‐of‐plane buckling defects and NW fractures, due to their rigid and brittle nature and nonuniform load transfer to specific points of NW. To resolve these problems, an alternative method is proposed to control the elastic modulus of 1D NW networks through contact with various solvents during compressive strain. Through solvent contact, the interface interactions between the NWs and between the NW and substrate can be controlled, and it is shown that the surface instability of the 1D random network is formed differently from a uniform bilayer film, which also can vary with the modulus of the network. For modulus values lower than the critical point, slippage and rearrangement of NW strands mainly occur and individual strands in the network show an in‐plane wavy configuration, which is ideal for structural stretchability. Based on the solvent‐assisted prestrain method, letter‐sized, large‐area stretchable, and transparent electrodes with high transparency and conductivity are achieved, and stretchable and transparent alternating current electroluminescent devices for stretchable display applications are also realized.     

Device architectures for improved amorphous polymer semiconductor thin-film transistors

In this letter, the performance characteristics of single-gate and dual-gate thin-film transistors (TFTs) with amorphous indenofluorene–phenanthrene copolymer semiconductor active layers are reported. Optimized single-gate devices possess mobilities up to 0.15 cm²/V-s and width-normalized contact resistance of 1275 Ωcm. These results were obtained through the combination of a recessed source/drain structure and suitable surface treatments of source/drain contact electrodes. The characteristics of dual-gate indenofluorene–phenanthrene copolymer TFTs with polymer gate insulators are also reported. This structure exhibits increased on-current, reduced threshold voltage, improved sub-threshold swing and increased on–off current ratio compared to single-gate architectures.     

Single‐Electron Pass‐Transistor Logic with Multiple Tunnel Junctions and Its Hybrid Circuit with MOSFETs

To improve the operation error caused by the thermal fluctuation of electrons, we propose a novel single‐electron pass‐transistor logic circuit employing a multiple‐tunnel junction (MTJ) scheme and modulate a parameters of an MTJ single‐electron tunneling device (SETD) such as the number of tunnel junctions, tunnel resistance, and voltage gain. The operation of a 3‐MTJ inverter circuit is simulated at 15 K with parameters C_g=C_T=C_clk=1 aF, R_T=5 MΩ, V_clk=40 mV, and V_in=20 mV. Using the SETD/MOSFET hybrid circuit, the charge state output of the proposed MTJ‐SETD logic is successfully translated to the voltage state logic.     

Property comparison of polarons in zinc-blende and wurtzite GaN/AIN quantum wells

The properties ofpolarons in zinc-blende and wurtzite GaN/AlN quantum wells with Fr(o)hlich interaction Hamiltonians are compared in detail.The energy shifts of polarons at ground state due to the interface (IF),confined (CO) and half-space phonon modes are calculated by a finite-difference computation combined with a modified LLP variational method.It is found that the two Fr(o)hlich interaction Hamiltonians are consistent with each other when the anisotropic effect from the z-direction and the x-y plane is neglected.The influence of the anisotropy on the polaron energy shifts due to the IF phonon modes for a smaller well width or due to the CO phonon modes for a moderate well width is obvious.In addition,the built-in electric field has a remarkable effect on the polaron energy shifts contributed by the various phonon modes.