Sorbents for the Direct Capture of CO2 from Ambient Air

The urgency to address global climate change induced by greenhouse gas emissions is increasing. In particular, the rise in atmospheric CO₂ levels is generating alarm. Technologies to remove CO₂ from ambient air, or “direct air capture” (DAC), have recently demonstrated that they can contribute to “negative carbon emission.” Recent advances in surface chemistry and material synthesis have resulted in new generations of CO₂ sorbents, which may drive the future of DAC and its large‐scale deployment. This Review describes major types of sorbents designed to capture CO₂ from ambient air and they are categorized by the sorption mechanism: physisorption, chemisorption, and moisture‐swing sorption.     

In Vivo Endoscopic Tissue Identification by Rapid Evaporative Ionization Mass Spectrometry (REIMS)

Gastrointestinal cancers are a leading cause of mortality, accounting for 23 % of cancer‐related deaths worldwide. In order to improve outcomes from these cancers, novel tissue characterization methods are needed to facilitate accurate diagnosis. Rapid evaporative ionization mass spectrometry (REIMS) is a technique developed for the in vivo classification of human tissue through mass spectrometric analysis of aerosols released during electrosurgical dissection. This ionization technique was further developed by utilizing surface induced dissociation and was integrated with an endoscopic polypectomy snare to allow in vivo analysis of the gastrointestinal tract. We tested the classification performance of this novel endoscopic REIMS method in vivo. It was shown to be capable of differentiating between healthy layers of the intestinal wall, cancer, and adenomatous polyps based on the REIMS fingerprint of each tissue type in vivo.     

CdS纳米粒子的表面修饰及其对光学性质的影响

用反胶束法合成了用表面活性剂分子磺基焉珀酸双－２－乙基已酯钠盐（ＡＯＴ）进行表面修饰的ＣｄＳ纳米粒子（记为ＣｄＳ／ＡＯＴ－ＳＯ３＾－）,研究了这种纳米粒子在正庚烷（ｈｅｐｔａｅ）和吡啶（Ｐｙ）溶剂中的荧肖及光解行为,发现其在正庚烷中荧光很强,而Ｐｙ却强烈地猝灭ＣｄＳ纳一子的荧光,用电荷转移猝灭机制进行了解释,这种解释为ＣｄＳ纳米粒子在Ｐｙ中光解实验进一步证实。     

Synthesis and Characterization of CdS Nanoparticles with Strong Electrolyte Behavior

The CdS nanoparticles whose structure is similar to a strong electrolyte were synthesized by the colloidal chemical method. The CdS nanoparticles with Cd²⁺-rich surface are capped by the electrically neutral ligand of 2,2-bipyridine (bpy), and the counterion, BPh₄ ^-, is adsorbed around the particle as balance charge. The donation from 2,2-bipyridine at 2-position to the Cd²⁺-rich surface of the CdS nanoparticles was characterized by X-ray photoelectron spectroscopy (XPS). These CdS nanoparticles can redisperse in pyridine (py) or DMF, and have high stability. The determination of electroconductivity and the electrophoresis deposition in dilute solution containing the CdS nanoparticles further prove the rationality of the above electrolyte structure of the CdS nanoparticles.     

On Studies of Crystal Structure and Electron Paramagnetic Resonance of(η5-C5H5)2Nb[CH2S(CH3)3]2

(η⁵-C₆H₅)₂Nb[CH₂Si(CH₃)₃]₂has been prepared and characterized by X-ray diffraction method and solution and frozen-glass EPR.The compound crystallizes in a monoclinic space group P2₁/Owith lattice parameters a=13.291(Å),b=12.406(Å),σ=13.901Å,β=115.40,V=2070Å⁵and Z=4 Full-matrix least-squares refinement of the diffractometry data led to final discrepancy indices of K(F₀)=0.043,R(F₀²)=0.057,R_w(F₀²)=0.071.From computer simulation of the frozen-glass spec trum of the compound,the principal components of the g and Ttensors are g_x=1.9840.g_y=2.0075,g_z=2.0020,T_x=-89.2G,T_y=-136.9G,T_z=-50.0G.The observed anisotropy for the hyperfine interaction arises from the admixture of 4d_z² and 4d_x²-y² character in the HOMO.The ratio of mixing coefficients a²/b²=10.3.     

有机金属化合物的振动光谱(Ⅱ)——1,1′-二甲基环戊二烯铁夹心化合物振动光谱的简正坐标计算

测定了(CH_3Cp)_2Fe(Cp=C_5H_4~-)夹心化合物的Fourier变换红外光谱和激光Raman光谱, 并做了指认, 将G-F矩阵法计算得到的Cp_2M(M=Mn,Fe,Ru)夹心化合物的一套力常数, 完整地转移到该分子上, 计算得到的振动光谱频率与测得的基本一致。     

Fabrication of nanoscale latex arrays based on hydroxylated poly(butyl methacrylate-<Emphasis Type="Italic">b</Emphasis>-glycidyl methacrylate)

We succeeded in fabricating nanoscale arrays of polymers based on hydroxylated poly(butyl methacrylate-b-glycidyl methacrylate) which was prepared via a novel atom-transfer radical polymerization technique. Nanosized latex particles of the copolymer were obtained in the tetrahydrofuran/toluene solvent system. By evaporation of the latex solution on a substrate, the ordered self-organization monolayer was formed. Rather regular, two-dimensional arrays of nanopaticles with diameters down to approximately 12 nm were observed by means of transmission electron microscopy. The regular nature of the arrays can be controlled well by depositing the monolayer at a lower temperature.     

Aggregation Behavior of Azoanthracene Compounds in Solution

Abstract

Aggregation of azoanthracene compounds 10-(4'-carboxylphenylazo)-9-anthranol and 10-(2'-carboxylphenylazo)-9-anthranol in solution was investigated by UV-vis spectroscopy. It was determined that the forming of a hydrogen bond, either intermolecular or intramolecular, can affect the wavelength of π-π? transition absorption. Using this principle the aggregation state of azoanthracene compounds was characterized.     

手性schiff碱金属配合物N,N′-双水杨醛缩-1,2-环己二胺合镍(Ⅱ)的光谱研究

利用红外、拉曼光谱研究一种手性schiff碱金属配合物N,N′双水杨醛缩1,2环己二胺合镍(Ⅱ)的结构特点。表明(R,R)—SALEN—Ni(Ⅱ)和(S,S)SALEN-Ni(Ⅱ)的光谱完全相同,而与外消旋体的光谱有很大差别     

血卟啉衍生物(HpD)的表面增强共振拉曼光谱

近年来,采用光敏剂(H_pD)与光的协同效应,诊治癌肿疾病有了较大的进展,所以,研究其光谱特性是有其现实意义的。 用共振拉曼光谱和表面增强拉曼光谱所获得的散射强度,都比通常的拉曼光谱有几个数量级的增强,并可得到稀溶液(10~(-6)～10~(-3)mol/L)的高质量光谱,本文报道了8×10~(-3)mol/L HpD水溶液的共振拉曼光谱和5×10~(-5)mol/L HpD水溶液的表面增强共振拉曼光谱,结果表明,表面增强共振拉曼光谱比共振拉曼光谱的散射强度滴出三个量级。