模糊决策器的硬件实现

本文提出了一种硬件实现模糊决策的方法，从理论上论证了这种方法的正确性，并通过实验证明其可行。它可以应用于模糊硬件系统，以实现对连续或离散模糊信号的去模糊。     

丙烯酸基蓖麻油氨基甲酸酯齐聚物的合成和表征

合成和表征了丙烯酸基蓖麻油氨基甲酸酯齐聚物(VTPU)。证明:2,4-甲苯二异氰酸酯(2,4-TDI)与丙烯酸羟乙酯(HEA)封端反应生成丙烯酸基单异氰酸酯(IPT)为二级反应。同样,ITP与蓖麻油(CAO)扩链反应亦为二级。通过对缩合反应速率常数和表观活化能的研究表明:VTPU的结构主要由2,4-TDI中对位和邻位二异氰酸基的活性差异所控制,而齐聚物表观粘度与二异氰酸酯的结构规整性有关。动态粘弹谱测试表明:当VTPU中硬链段含量为59%时,聚合物呈分相结构,抗张强度最高为18.2MPa,若增加至67%时,在100.7℃呈现单一转变峰,动态模量因而下降。     

超高速光时分复用技术实现及发展

以单波道160Gbit／s传输为例，介绍了光时分复用技术的基本原理，对其中的关键技术进行了分断、比较，并对更高速的OTDM传输技术做了探讨。     

CaO solubility and activity coefficient in molten salts CaCl2–x (x = 0, NaCl, KCl, SrCl2, BaCl2 and LiCl)

CaO solubility in equimolar molten salts CaCl₂–x (x = 0, NaCl, KCl, SrCl₂, BaCl₂ and LiCl) was determined at 873–1223 K and activity coefficient calculated. CaO solubility in the binary salts is less than in CaCl₂, and the activity coefficient is greater than one. With increasing temperature CaO solubility increases and the activity coefficient decreases. The dependency of CaO activity coefficient on temperature in equimolar molten salts CaCl₂–x is

CaCl2	RTln γCaO = 6961 + 5.06 T (K)	1123–1223 K
CaCl2–NaCl	RTln γCaO = 3985 + 17.67 T (K)	923–1123 K
CaCl2–KCl	RTln γCaO = 2384 + 22.72 T (K)	1073–1223 K
CaCl2–SrCl2	RTln γCaO = 27245–1.13 T (K)	1073–1223 K
CaCl2–BaCl2	RTln γCaO = 17068 + 10.19 T (K)	1223–1273 K
CaCl2–LiCl	RTln γCaO = 14724 + 0.72 T (K)	923–1073 K

Full-size table

     

A Reagentless Electrochemical DNA Sensor Based on a Self-powered DNA Machine

Herein, a reagentless electrochemical DNA sensor based on a self-powered DNA machine for detecting survivin mRNA in cells is developed. The metal-organic framework (MOFs) loaded with DNAzyme cofactors (Mn²⁺) is coated on PTFE rods on the Au surface and assembled with the DNA walker, overcoming the complexity of adding metal ions from the external environment. In addition, the orbital chain is modified by a synthetic bisferrocene signal marker, which further enables signal amplification. Under optimal conditions, the sensor exhibits a range from 1×10⁻¹⁴ mol/L to 1×10⁻⁸ mol/L with a detection limit (S/N=3) of 1.28 fM.     

Electrochemical Interfacial Polymerization toward Ultrathin COF Membranes for Brine Desalination

Ultrathin covalent organic framework (COF) membranes are urgently demanded in molecular/ionic separations. Herein, we reported an electrochemical interfacial polymerization strategy to fabricate ultrathin COF membranes with thickness of 85 nm, by actively manipulate self-healing effect and self-inhibiting effect. The resulting COF membrane exhibited superior performance in brine desalination with the permeation flux of 92 kg m⁻² h⁻¹ and the rejection of 99.96 %. Our electrochemical interfacial polymerization strategy enriches the fabrication approach of COF membranes and facilitates the rational design of ultrathin membranes.     

电极表面第二配位环境对水氧化分子催化剂O–O键形成机理的调控

水氧化反应可以提供四个电子和四个质子,反应产物是可以资源化的氧气,因而,水氧化反应是大规模能源转化和存储技术理想的阳极反应.但是,由于水氧化反应具有较高的热力学能垒,涉及四个电子和四个质子的转移过程以及氧-氧键(O–O)的形成,是一个耗能高且动力学缓慢的复杂反应.因此,开发高效的水氧化催化剂来加速水氧化反应速率,对于能源转化和存储相关技术至关重要.然而,人们对水氧化催化剂的合理设计和在催化反应中提高反应活性的方法了解甚少,在温和条件下促进O–O键的有效形成仍然是一个根本性的挑战.迄今为止,关于水氧化分子催化剂的研究主要集中在催化剂的配位结构(第一配位环境)和催化效率之间的关系上,水氧化分子催化剂的第二配位环境对其催化活性的影响尚未得到充分研究.将催化剂引入到电极表面时,其催化环境和均相反应时完全不同.因此,水氧化催化剂在电极表面的催化反应动力学、质子耦合电子转移过程以及其O–O键形成机理可能发生改变.本文以4-乙烯基吡啶为轴向配体的[Ru(bda)](络合物1,bda=2,2’-联吡啶-6,6’-二羧酸)水氧化分子催化剂,通过电化学聚合的方法将络合物1固载在玻璃碳电极表面,用于研究第二配位环境对电极表面水氧化分子催化剂催化机理的影响.通过直接聚合络合物1在玻璃碳表面得到电极材料poly-1@GC;将4-三氟甲基苯乙烯和苯乙烯作为限制单元分别与络合物1共聚,得到电极材料poly-1+P3F@GC和poly-1+PSt@GC.通过一系列电极表面动力学方法和DFT计算分别求出催化剂在三种电极材料中的反应级数ρcata、催化剂的溶液质子-原子转移性质、催化剂的水氧化氘动力学同位素效应KIEs_H/D,以及[Ru(bda)]催化剂在不同材料中的偶极矩的变化.通过对比催化剂在不同电极材料中的催化行为和相关关键参数发现,电极表面催化剂的第二层配位环境对其水氧化反应过程中的O–O键形成机制和质子耦合电子转移过程有着显著的影响.[Ru(bda)]在直接聚合的电极材料poly-1@GC中,通过自由基耦合机理(I2M)形成O–O键.而当[Ru(bda)]与4-三氟甲基苯乙烯和苯乙烯共聚时,由于[Ru(bda)]催化剂被分散,不利于自由基耦合机理的发生,[Ru(bda)]在电极材料poly-1+P3F@GC和poly-1+PSt@GC中主要通过水分子亲核进攻机理进行(WNA)催化水氧化.同时,具有强偶极矩的4-三氟甲基苯基能够稳定[Ru(bda)]在催化过程的中间体,可以使引发O–O键生成的关键物种Ru^V=O的氧化电位发生明显的负向移动,使得[Ru(bda)]在poly-1+P3F@GC可以更容易触发水氧化反应,进而加快了[Ru(bda)]采用水分子亲核进攻机理时的催化反应速率.     

Syntheses, structures and properties of a series of non-heme alkoxide-Fe(III) complexes of a benzimidazolyl-rich ligand as models for lipoxygenase

The treatment of Fe(ClO(4))(2)·6H(2)O or Fe(ClO(4))(3)·9H(2)O with a benzimidazolyl-rich ligand, N,N,N',N'-tetrakis[(1-methyl-2-benzimidazolyl)methyl]-1,2-ethanediamine (medtb) in alcohol/MeCN gives a mononuclear ferrous complex, [Fe(II)(medtb)](ClO(4))(2)·?CH(3)CN·?CH(3)OH (1), and four non-heme alkoxide-iron(III) complexes, [Fe(III)(OMe)(medtb)](ClO(4))(2)·H(2)O (2, alcohol = MeOH), [Fe(III)(OEt)(Hmedtb)](ClO(4))(3)·CH(3)CN (3, alcohol = EtOH), [Fe(III)(O(n)Pr)(Hmedtb)](ClO(4))(3)·(n)PrOH·2CH(3)CN (4, alcohol = n-PrOH), and [Fe(III)(O(n)Bu)(Hmedtb)](ClO(4))(3)·3CH(3)CN·H(2)O (5, alcohol = n-BuOH), respectively. The alkoxide-iron(III) complexes all show 1) a Fe(III)-OR center (R = Me, 2; Et, 3; (n)Pr, 4; (n)Bu, 5) with the Fe-O bond distances in the range of 1.781-1.816 ?, and 2) a yellow color and an intense electronic transition around 370 nm. The alkoxide-iron(III) complexes can be reduced by organic compounds with a cis,cis-1,4-diene moiety via the hydrogen atom abstraction reaction.     

Low-temperature diffusion of oxygen through ordered carbon vacancies in Zr2C(x): the formation of ordered Zr2C(x)O(y)

Investigations are performed on low-temperature oxygen diffusion in the carbon vacancy ordered ZrC(0.6)and thus induced formation of the oxygen atom ordered ZrC(0.6)O(0.4). Theoretically, a superstructure of Zr(2)CO can be constructed via the complete substitution of carbon vacancies with O atoms in the Zr(2)C model. In the ordered ZrC(0.6), the consecutive arrangement of vacancies forms the vacancy channels along some zone axes in the C sublattice. Through these vacancy channels, the thermally activated oxygen diffusion is significantly facilitated. The oxygen atoms diffuse directly into and occupy the vacancies, producing the ordered ZrC(0.6)O(0.4). Relative to the ordered ZrC(0.6), the Zr positions are finely tuned in the ordered ZrC(0.6)O(0.4) because of the ionic Zr-O bonds. Because of this fine adjustment of Zr positions and the presence of oxygen atoms, the superstructural reflections are always observable in a selected area electron diffraction (SAED) pattern, despite the invisibility of superstructural reflections in ZrC(0.6) along some special zone axes. Similar to the vacancies in ordered ZrC(0.6), the ordering arrangement of O atoms in the ordered ZrC(0.6)O(0.4) is in nanoscale length, thus forming the nano superstructural domains with irregular shapes.