内敏乳剂的感光性能和离子性能

本文研究了内核经硫加金增感的内敏核壳乳剂的感光性能和离子性能。内核化学增感时Ｎａ２Ｓ２Ｏ３和ＡｕＣｌ３两者的加入量按一定比例增大时，内部感光度升高，表面感光度下降，离子电导率略有降低。内核化学增感时如果单独增加ＡｕＣｌ３的用得，内部感光度有所升高，表面感光性能基本不变，离子电导率略有下降。内核化学增感结束引入稳定剂５８３，可使内显灰雾明显降低，离子电导率也有所下降。核壳比增大造成内部感光度上升而表     

AgBr核壳乳剂的颗粒内部还原增感与表面化学增感的协同增感效应

采用对核颗粒进行还原掺杂和将其包壳的方法制备了一系列不同DMAB用量、内部有还原敏化中心(Ag2)的AgBr核壳乳剂．这些乳剂表现出明显的增感效应．当这些乳剂分别进行表面硫、金和硫加金增感后，一方面表现出明显的协同增感效应；另一方面又随DMAB用量的提高，灰雾明显增长，特别是在金增感和硫加金增感的情况下、此外实验结果还证明，提高核乳剂的包壳速率可以在一定程度上减少核壳乳剂的灰雾。     

ESR信号的衰减与超增感机理的研究

ＥＳＲ信号的衰减与超增感机理的研究张金龙，朱正华（华东理工大学精细化工研究所，上海２００２３７）关键词ＥＳＲ，正穴，衰减动力学，超增感机理众所周知，超增感机理在感光化学中起着极其重要的作用，因此成为广大感光科学工作者研究的一大热点，先后提出了各自的设...     

染料的吸附对超增感作用的影响

研究了实用乳剂中增感染料和超增感染料的吸附状态对乳剂感光性能的影响，并测试了ＥＳＲ信号。实验证实了只有当增感染料和超增感染料同时吸附在乳剂上时，感光度才最高，ＥＳＲ信号亦最强。     

阴离子对染料增感作用的影响

通过地含有不同阴离子的３，３′，９－三乙基－４，５，４′，５′－二苯并硫碳菁染料的乳剂试验，研究了染料阴离子对感光度，染料的聚集态，增感峰和增感范围，染料吸附等温线和电子顺磁共振（ＥＳＲ）信号的影响。     

Ti(C,N)基金属陶瓷中陶瓷相芯/壳组织的观察与分析

用ＸＲＤ，ＳＥＭ，ＴＥＭ和ＨＲＥＭ观察、分析和方法研究了Ｔｉ（Ｃ，Ｎ）基金属陶瓷中陶瓷相的芯、壳组织。结果表明，在ＳＥＭ，ＴＦＭ观察中，芯、壳之间存在相界面，而ＨＲＥＭ观察显示陶瓷相的芯／壳组织具有连续相同的点阵结构。     

新型亚磺酰胺类化合物在照相乳剂中的应用

研究了系列新型亚磺酰胺类化合物与增感染料在实用照相乳剂中的超增感作用。实验结果表明，照相乳剂的感光度有明显的提高，增感效果高于某些常用的超增感剂。通过ＥＳＲ信号及极谱半波电位的测试，对超增感机理进行了解释。     

新型亚磺酰胺类化合物的在照相乳剂中的应用

研究了系列新型亚磺酰胺类化合物一增感染料在实用照相乳剂中的超增感作用。实验表明，照相乳剂的感光度有明显的提高，增感效果高于某些常用的超增感剂。通过ＥＳＲ信号及极谱半波电全的测试，艰超增感机理进行了解释。     

CPE与ACR或MBS复合增韧R—PVC体系的流变性能研究

本文主要研究了ＣＰＥ／ＡＣＲ、ＣＰＥ／ＭＢＳ复合增韧ＲＰＶＣ体系的熔体剪切粘度（ηα）与增韧剂组成比（Ｒｃ）的关系。结果表明,两种三元共混物的ηαＲｃ关系明显不同;定Ｒｃ和γ下的ηα,ＣＰＥ／ＡＣＲ体系＜ＣＰＥ／ＭＢＳ体系;该ηα差别随Ｒｃ增加而增大,随γ增加而减小。其流变特性与增韧组份间相互作用和相分散形态有关。     

锡偶联溶聚丁苯橡胶塑炼过程的力化学研究

研究了国产锡偶联溶聚丁苯橡胶（ＳＳＢＲ）在加工过程中相对分子质量、相对分子质量分布及微观结构的变化,并与乳聚丁苯橡胶（ＥＳＢＲ）进行了比较。结果表明,在塑炼过程中相对 ＳＳＢＲ和ＥＳＢＲ相对分子质量的下降速度与初始相绎分子质量有关,相对分子质量存在下限值;ＳＳＢＲ的相对分子质量分布曲线由双峰转化成单峰,并变窄;ＳＳＢＲ和ＥＳＢＲ的主链断裂,产生过氧自由基,ＳＳＢＲ的塑炼过程力化学稳定性优于ＥＳＢＲ     

Evolution of microstructure and combustion reactivity of lignite during high-temperature drying process

The evolutions of the microstructure characteristics and the combustion reactivity of lignite during high temperature drying process at 600–800°C were addressed in the paper. The information about the oxygen functional groups, carbon skeleton, pore structure, and combustion reactivity of the lignite before and after the drying treatment was obtained by Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller technique, Raman spectroscopy and thermogravimetric analyzer, respectively. The results show that a different evolutionary trend of the chemical structure of the lignite appears at the high drying temperature of 700°C at which the carbonyl, carboxyl, and carboxylate significantly decomposed and the treatment gave a slight elimination of structural imperfections and the formation of new cross-linking structures. Then, at the drying temperature of 800°C, a slight increase of the oxygen functional groups was found. The break of the aromatic ring or heterocycle contributed to the rapid increase of amorphous carbon to some extent. During the drying process, the surface area of the resulted lignite gradually increased until 700°C and then decreased. The evolution may be attributed to the decomposition of organic compounds, shrinkage forces, and thermal relaxation effect. The investigation indicates that the change in chemical nature of the coal had a greater impact on the combustion reactivity than the internal pore structure did. In addition, the combustion intensity and performance of the treated lignite was enhanced by the drying process.     

Synthesis of sequential poly(1,3-phenyleneethynylene)-based polyradicals and through-space antiferromagnetic interaction of their solid state

Some 1,3-PPE-based polyradicals with pendent phenoxy radicals whose repeating unit consisted of four 1,3-phenyleneethynylene units were synthesized via polymerization between monomers and trimeric monomers in the presence of the Pd(PPh₃)₄ complex catalysts. The ESR spectra of the polyradicals in dichloromethane showed unimodal broad signals. For the solid samples which were prepared from the dichloromethane solution by evaporating the solvent and by drying in vacuo, the signal intensity decreased with broadening of peak-to-peak line-width (ΔH_pp). However, the ESR spectra almost recover to the initial intensity and shapes due to redissolving in dichloromethane. In particular, the decrease of doubly integrating the ESR signal (I_ESR) was more remarkable for the polyradical bearing galvinoxyl and phenoxyl residues than others. This behavior suggests that strong antiferromagnetic interaction partially arose for the polyradical.     

A study of the adhesion of thiokol-epoxy hermetics to a brass and an aluminum alloy substrate

The conditions under which hermetics can be used depend largely on the nature of the bond between the polymer and the substrate. Here we have studied the thiokol-epoxy compositions and have investigated the processes taking place at the interface between the hermetic and a brass or an aluminum alloy substrate. To establish the nature of interfacial interactions electron spin resonance (ESR) spectroscopy was utilized. The ESR spectrum of the species from the interface layer is assigned to a bivalent copper ion complex, sulfur-containing fragments being the ligands. The ESR signal intensity of the complex was maximum for the case of the brass substrate and minimum for the aluminum alloy substrate; no spectrum was detected for the glass substrate or for the bulk hermetic. The dependence of the ESR signal intensity on the free sulfur content in the hermetic was found to be opposite to the dependence of the adhesion values.     

Effect of γ Radiation on High-Water-Content-Glasses

Na₂O−3SiO_z-glasses containing up to ∼11 wt% water were prepared under high-pressure, hydrothermal conditions. The samples were exposed to γ radiation of 5 × 10⁷ rad. Optical and ESR measurements were made before and after exposure to radiation and it was found that the induced absorption in the visible region decreased drastically with increasing H₂O concentration. The induced ESR signal-integrated intensity also decreased with increasing water content. After irradiation an increase was observed in the fundamental OH absorption bands in the ir region of the spectra of the water-containing specimens.     

Oxidation behavior and mechanism of aluminum oxynitride (AlON) at elevated temperatures

The oxidation behavior and mechanism of aluminum oxynitride (AlON) powder exposed to air at elevated temperatures between 800°C and 1300°C was investigated by X-ray diffractometry (XRD), scanning electron microscope (SEM), electron spin resonance (ESR), nuclear magnetic resonance (NMR), and simultaneous thermogravimetry, differential thermal analysis, and mass spectrometry techniques (TG-DTA-MS). The weight of AlON gradually increases to a maximum value at 1150°C and then decreases with further heating. Meanwhile, AlON powder undergoes chemical changes, as evidenced by lattice expansion, and turns eventually into alumina. ESR spectra reveal the occurrence of lone pair electrons in the oxidized products and the intensity of corresponding resonance signal increases before disappearing with the increase in temperature. Combined with the results of NMR and TG-DTA-MS, the measured data suggest that Al-N in [AlO₃N] tetrahedron and [AlO₅N] octahedron are gradually oxidized into Al-O-N group with lone pair electrons, which causes continuous weight gain and lattice expansion. Further oxidation at higher temperatures results in alumina and N₂.     

新型水溶性硫杂蒽酮类光引发剂的光化学性能研究

本文对８种水溶性硫杂蒽酮类光引发剂进行了紫外－可见光谱，荧光光谱以及电子自旋共振光谱（ＥＳＲ）等测试。测定了最大吸收波长，计算了摩尔消光系数，荧光量子产率，测定了ＥＳＲ信号强度等，并对其结构与光化学性能之间的关系进行了讨论。     

ESR Study of Cerium (IV) Oxide in Vacuum Air and Hydrogen

Cerium (IV) oxide prepared at high temperatures in air shows ESR absorption signals. The oxide prepared at low temperatures shows very diffuse signals. Heating the oxide in vacuum at 1000° or in hydrogen at 298° results in a reduction of the intensity of the signal. A theory was developed to show that the ESR signal is obtained from the quasi free electron in non-stoichiometric ceria.     

Structural insights of mechanically induced aluminum-doped hydroxyapatite nanoparticles by Rietveld refinement

Aluminum doped hydroxyapatite(HA:Al~(3+)) nanopowders were successfully prepared via a simple and efficient one-pot mechanochemical route. The effects of dopant loading on phase compositions and structural features were assessed by Rietveld analysis. The XRD-Rietveld refinement revealed the stabilization of HA in hexagonal structure for all the samples. The sharpness and intensity of the apatite-derived XRD peaks decreased as the dopant content increased to 10% due to the increase in lattice imperfections and mechanically induced amorphization. The incorporation of Al3+into the HA lattice decreased the unit cell parameters. From the FTIR measurements, the representing bands of apatite were identified in all cases. The mechanosynthesized nanopowders consisted of nanospheroids with an average size of 44 ± 20 nm and therefore are promising for bone tissue regeneration.     

XPS and ESR studies of the photodegradation of polyamidoimide and polyimide in O2, O2 + N2, air,N2, and vacuum atmospheres

The photostability of polyamidoimide (PAI) and polyimide (PI) films has been studied. UV irradiation caused a great change in the composition and structure of the film surface. With irradiation in atmospheres such as air, oxygen, and an oxygen—nitrogen mixture, the Cls spectrum had a distinct structure at high binding energy, and the O/C and N/C ratios were considerably increased. On the other hand, in nitrogen and under vacuum, the O/C and N/C ratios remained almost unchanged during an earlier stage of irradiation, but in the latter stage for the nitrogen atmosphere these ratios decreased to a broad minimum and then increased with an increase of irradiation time. UV irradiation also produced free radicals in the polymer films; PAI gave a much stronger ESR signal intensity than PI. The signal intensity vs. irradiation time curve was strongly influenced by irradiation atmospheres. In atmospheres containing oxygen the curve exhibited a broad maximum during an initial stage of irradiation, while under vacuum and in nitrogen the signal intensity increased greatly in the latter stage. The formation of free radicals during an earlier stage of irradiation in atmospheres containing oxygen was promoted by the oxygen incorporated at the film surface, while the radical production under vacuum was considered to be due to rupturing of bonds in the bulk material. The decay of free radicals in the dark after irradiation occurred at a faster speed in oxygen atmospheres than under vacuum.     

Saccharide radicals induced by UV irradiation at room temperature

The stability of saccharide radicals induced by UV irradiation at room temperature and the ability to initiate polymerization of acrylamide were investigated. UV light of 220 < λ < 300 nm was proved to form saccharide radicals effectively at room temperature. ESR signal intensity of the irradiated saccharide was in the order of sucrose > methyl-α-D-glucopyranoside ? cellobiose > D-xylose > D-glucose α D-fructose. The saccharide radicals were fairly stable at room temperature, however, the markedly declined in amount as the samples were brought to their own melting points or allowed contact with water. When an aqueous solution of acrylamide was added to the irradiated saccharide, polymerization was initiated and the conversion increased with an increasing amount of the preirradiated saccharide. Regarding the kind of saccharide, the conversion decreased in the following order: sucrose > methyl-α-D-glucopyranoside > cellobiose > D-glucose, which indicated a good agreement with the magnitude of ESR signal intensity.