NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 48
·期 38
·16776-16794
·
IF 2.7
Jianwei Zhang,Chengming Bian,Ling Chen,Weidong He
Recently, we investigated the interaction mechanism of 1H-tetrazole (1H-TZ) and nitrocellulose (NC). Next, we tried to introduce an amino group at the C and N atoms of 1H-tetrazole, so as to explore the influence of amino group modification on the pyrolysis process of NC. The focus of this study was on investigating the interaction mechanism of aminotetrazole (5-ATZ or DATZ) and NC through kinetics methods and TG-DSC-FTIR analysis. The quenching and reheating experiments revealed that the imino form of 5-ATZ or DATZ played an important role in this process. The addition of aminotetrazole (5-ATZ and DATZ) mainly affected the autocatalytic reaction at the initial stage of the pyrolysis process of NC. TG-DSC-FTIR experiments revealed that there was a chemical reaction between NO2 and decomposition products of 5-ATZ or DATZ. In this reaction, R–NCNH or NC–NH–R (R = H and NH2) reacted with NO2 to form N2O and CO2.
研究领域:
化学动力学
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材料科学
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热分析
✓ 已验证
产品关联
DOI
高影响因子
ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE
·
2021
·Vol. 647
·期 12
·1269-1276
·
IF 1.492
Jiayuan Zhang,Xiao Zhao,Yuandong Wu,Dajiang Mei,Shaoguo Wen,Thomas Doert
Two new antimony (III) tellurite sulfates [Sb 2 (TeO 4 )](SO 4 ) ( 1 ) and [Sb 2 (TeO 3 ) 2 ](SO 4 ) ( 2 ) were successfully synthesized through a conventional hydrothermal method and their crystal structures were determined by X-ray single crystal analysis. [Sb 2 (TeO 4 )](SO 4 ) crystallizes in the triclinic space group P ī (No. 2) with lattice parameters a=5.572(2), b=7.247(2), c=9.540(3) Å, V=358.5(2) Å 3 , and Z=2, while [Sb 2 (TeO 3 ) 2 ](SO 4 ) crystallizes in the orthorhombic space group Pbca (No. 61) with lattice parameters a=7.368(2), b=14.571(3), c=16.521(3) Å, V=1773.7(6) Å 3 , and Z=8. The structure of [Sb 2 (TeO 4 )](SO 4 ) features a three-dimensional framework, composed of [SbO 4 ] trigonal bipyramids and [TeO 4 ] polyhedra to form a cationic 2 ∞[Sb 2 (TeO 4 )] 2+ corrugated cationic layers along [100], linked by SO 4 2− anions. [Sb 2 (TeO 3 ) 2 ](SO 4 ) forms a three-dimensional framework consisting of two dimensional wrinkled layers of 2 ∞[Sb 2 (TeO 3 ) 2 ] 2+ that are linked by SO 4 2− anions. The band gaps of 4.16 eV and 3.72 eV for [Sb 2 (TeO 4 )](SO 4 ) and [Sb 2 (TeO 3 ) 2 ](SO 4 ) respectively are estimated from the solid state UV-vis-NIR diffuse reflectance spectra. Thermal analysis indicated that both compounds are thermally stable up to about 500 °C. The electrochemical specific capacity of [Sb 2 (TeO 4 )](SO 4 ) was determined to 245 mA h g −1 on the first cycle in a Li-ion half-cell, the capacity remains at about 106 mA h g −1 after 500 cycles.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY
·
2018
·Vol. 99
·期 2
·e21499
·
IF 1.316
Lin Zhu,De-Qing Zou,Zuo-Qing Fan,Na Wang,Ying-Ying Bo,Yu-Qing Zhang,Guang Guo
In this study, a carboxymethyl chitosan derived from silkworm pupa (SP-carboxymethyl chitosan) was prepared. The physical characteristics of the SP chitin, chitosan, and carboxymethyl chitosan were analyzed. The scanning electron microscopy results showed that the surfaces of the samples from SP were more uneven, with more surface fractures compared with those of the reference substance (RS). Thermal analysis, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy analysis showed that the main molecular chain structures of SP samples and RSs had no substantial differences. However, the crystallinity and thermal decomposition temperature of the SP samples were lower compared with those of the RSs. All of these results provide a theoretical basis for the development of applications for the SP-carboxymethyl chitosan.
研究领域:
生物材料学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 54
·期 5
·4115-4123
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IF 2.993
Zhou Xiang,Zhu Ying,Ke Xiang,Zhang Kaili
In this study, we use simultaneous differential scanning calorimetry and thermogravimetric analysis to analyze the solid-state reaction characteristics of Al/Fe 2 O 3 nanothermites before n -Al melts. Different experimental setups for thermal analysis are compared, and the heat-release characteristics are studied on Al/Fe 2 O 3 nanothermites in the form of powder and pellet, respectively. It is found that protection provided by mere argon flow is far from enough for thermal analysis of Al/Fe 2 O 3 nanothermites. The experimental setup must be free of oxygen; otherwise, the determined exothermic peak is mostly the oxidation of n -Al by the residue oxygen molecules in the furnace body, due to the high reactivity and moderate accessibility of free oxygen molecules. Under proper experimental setup, it is found that besides the redox reaction between n -Al and n -Fe 2 O 3 , intermetallic reaction also occurs to form Fe 4 Al 13 . Moreover, the intermetallic reaction is more noticeable for nanothermite pellet than for nanothermite powder, and the eutectic reaction of Fe 4 Al 13 and n -Al leads to melting peaks below 655 °C. The results indicate that instrument configuration and sample status affect the testing results to a large extent, and one should be prudent to derive reaction characteristics of nanothermites.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE
·
2020
·Vol. 646
·期 20
·1688-1695
·
IF 1.24
Shuangsheng Cheng,YuanDong Wu,Dajiang Mei,Shaoguo Wen,Thomas Doert
Four alkali metal bismuth sulfates, NaBi(SO 4 ) 2 · H 2 O ( 1 ) and ABi(SO 4 ) 2 [A = K ( 2 ), Rb ( 3 ), Cs ( 4 )], were successfully synthesized by hydrothermal methods. The crystal structure of 1 features a three-dimensional tunnel framework constructed by BiO 9 tri-capped trigonal prisms and SO 4 tetrahedra interconnected via common corners and edges. Compound 2 exhibits a two-dimensional 2 ∞ [Bi(SO 4 ) 2 ] – double-layered structure, assembled by one-dimensional 1 ∞ [BiS(1)O 4 ] + chains which are linked via S(2)O 4 2– tetrahedra. The isostructural compounds 3 and 4 possess a two-dimensional layered structure, and the layers being composed by BiO 8 square antiprism and SO 4 tetrahedra. The alkali metal cations are located between the layers or in the tunnels of the structures, respectively. The differences in the crystal structures of the title compounds can mainly be attributed to the different sizes of the alkali metal cations and their different coordination environments. Thermogravimetric analysis evidence that compound 1 losses one equivalent of water at 120 °C whereas the anhydrous compounds 2 – 4 are stable up to about 450, 575, and 578 °C, respectively. The solid-state UV/Vis/NIR diffuse reflectance spectra indicate bandgaps of approximately 4.48, 4.43, 3.98, and 3.96 eV for compounds 1 – 4 , respectively.
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2021
·Vol. 13
·期 24
·4336
·
IF 4.329
Jolanta Tomaszewska,Tomasz Sterzyński,Aneta Woźniak-Braszak,Michał Banaszak
This review addresses the impact of different nanoadditives on the glass transition temperature (Tg) of polyvinyl chloride (PVC), which is a widely used industrial polymer. The relatively highTglimits its temperature-dependent applications. The objective of the review is to present the state-of-the-art knowledge on the influence of nanofillers of various origins and dimensions on theTgof the PVC. TheTgvariations induced by added nanofillers can be probed mostly by such experimental techniques as thermomechanical analysis (TMA), dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and dielectric thermal analysis (DETA). The increase inTgis commonly associated with the use of mineral and carbonaceous nanofillers. In this case, a rise in the concentration of nanoadditives leads to an increase in theTgdue to a restraint of the PVC macromolecular chain’s mobility. The lowering ofTgmay be attributed to the well-known plasticizing effect, which is a consequence of the incorporation of oligomeric silsesquioxanes to the polymeric matrix. It has been well established that the variation in theTgvalue depends also on the chemical modification of nanofillers and their incorporation into the PVC matrix. This review may be an inspiration for further investigation of nanofillers’ effect on the PVC glass transition temperature.Keywords:nanocomposites;thermal analysis;thermal properties;PVC glass transition
研究领域:
材料科学
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高分子化学
✓ 已验证
DOI
PubMed
高影响因子
Polymers
·
2015
·Vol. 7
·期 5
·896-908
·
IF 3.681
Ting Huang,Bo Jin,Ru Fang Peng,Cong Di Chen,Rong Zong Zheng,Yi He,Shi Jin Chu
A new functionalized [60]fullerene-glycidyl azide polymer (C60-GAP) was synthesized for the first time using a modified Bingel reaction of [60]fullerene (C60) and bromomalonic acid glycidyl azide polymer ester (BM-GAP). The product was characterized by Fourier transform infrared (FTIR), ultraviolet-visible (UV-Vis), and nuclear magnetic resonance spectroscopy (NMR) analyses. Results confirmed the successful preparation of C60-GAP. Moreover, the thermal decomposition of C60-GAP was analyzed by differential scanning calorimetry (DSC), thermogravimetric analysis coupled with infrared spectroscopy (TGA-IR), andin situFTIR. C60-GAP decomposition showed a three-step thermal process. The first step was due to the reaction of the azide group and fullerene at approximately 150 °C. The second step was ascribed to the remainder decomposition of the GAP main chain andN-heterocyclic at approximately 240 °C. The final step was attributed to the burning decomposition of amorphous carbon and carbon cage at around 600 °C.Keywords:C60;glycidyl azide polymer (GAP);thermal analysis;energetic material
研究领域:
化学
·
材料科学
✓ 已验证
DOI
高影响因子
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
·
2021
·
IF 3.927
Yihang Dong,Zhaoyang Liu,Guoxing Qiu,Lipeng Pang,Ye Han,Shuyu Yao,Jianxu Ding,Xiangnan Wang
{(ZrO 2 ) 0.92 (Y 2 O 3 ) 0.08 } 1- x (Cr 2 O 3 ) x solid solution is composed by co-precipitation method and the effects of Cr 2 O 3 content on thermal analysis, crystal structure, microstructure and electrical conductivity are researched. The results discuss the potential for application as a diffusion barrier material at temperatures between 600 and 850 °C to the limiting current oxygen sensors. TG and DSC results show that the main weight loss and heat absorption processes occur below 600 °C and the {(ZrO 2 ) 0.92 (Y 2 O 3 ) 0.08 } 1- x (Cr 2 O 3 ) x solid solution is obtained above 600 °C. XRD analysis shows that the solid solution is fluorite type cubic phase and the solubility of Cr 2 O 3 in (ZrO 2 ) 0.92 (Y 2 O 3 ) 0.08 is less than 0.10. The SEM-EDS results show that the grain size of the sintered body decreases with increasing Cr 2 O 3 content and distribution of each element is uniform. The conductivity of solid solution decreases first and then increases as Cr 2 O 3 doping content, reaches the maximum value of 4.33 × 10 −3 S cm −1 at 850 °C. The doping of Cr 2 O 3 is beneficial to improve the conductivity of the solid solution at low temperature.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
COMBUSTION AND FLAME
·
2021
·
IF 4.185
Chun Zhang,Huiqing Mao,Rui Cui,Xiandie Zhang,Jing Yang,Jie Ji,Xiang Zhou
High content of active component, low electrostatic sensitivity and superior long-term storage stability endow n-Si powder unique advantages for application in nanoenergetic composites. In this study, hydrophobic and corrosion-resistant Si@PVDF nanostructured energetic films with different stoichiometric ratios are successfully prepared by electrospinning technique . The energetic characteristics are systematically investigated in terms of thermal analysis, open-air combustion and constant-volume combustion. The results show that Si@PVDF films are microscopically composed of fibers with diameters of about 200–300 nm. With the increase of stoichiometric ratio, more and more n-Si aggregates are found on the surface of fibers. When Si@PVDF is stored in deionized water (50 °C) or NaOH solution (50 °C, 3 mol/L) for 72 h, around 100% and 73.3% of n-Si is retained. Si@PVDF can be thermally ignited, with appreciable heat and pressure output, and the combustion behaviors are strongly affected by the stoichiometric ratio and the environmental conditions. As a comparison, physically mixed Si/PVDF cannot maintain a self-sustained combustion. Through the coupled thermal analysis and mass spectrometry analysis, combined with the morphological and structural characterization of the solid residues , the reaction mechanism of Si@PVDF at a low heating rate is preliminarily obtained.
研究领域:
材料科学
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能源材料
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燃烧化学
✓ 已验证
DOI
高影响因子
CATALYSIS TODAY
·
2022
·
IF 6.562
Shihang Meng,Xiaoxiao Xue,Yujing Weng,Siyi Jiang,Guang Li,Qi Sun,Yulong Zhang
Molybdenum carbide is a noble-metal-like material, which shows great potential in many applications. The conventional Temperature-Programmed-Reduction (TPRe) method uses carbonaceous gases to carburize with molybdenum precursors, which has made a significant progress but still hard to scale up. In this work, molybdenum carbides were prepared by carburization of ammonium molybdenum molybdate on cellulose, g-C 3 N 4 , MWCNTs and sodium lignosulfonate without using any gaseous carbon source. Moreover, the formation of molybdenum carbide was subjected to in-depth investigation by using an in situ Simultaneous Thermal Analyzer – Quadrupole Mass Spectrometry coupling System. The technique revealed that the solid carbon carriers do have a great effect on the formation of molybdenum carbides. Furthermore, various characterization methods such as XRD, SEM, CO-TPD, FTIR and organic element analysis (OEA) were also applied to investigate the property of prepared molybdenum carbides. The results suggested that the prepared molybdenum carbides with CEL, MWCNTs and SLF as carbon supports could retain the skeleton and porous structure of a solid carbon carrier, and the prepared molybdenum carbides with g-C 3 N 4 as a carbon support could generate a new three-dimensional (3D) structure support, and the composition of carriers would also have an impact on the adsorption and physicochemical properties of molybdenum carbides.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS
·
2023
·Vol. 23
·期 3
·1362
·
IF 3.9
Haozhi Zhang,Hao Jia,Weiwen Feng,Zao Ni,Pengcheng Xu,Xinxin Li
Ultra-responsive single-crystal silicon MEMS thermopiles for differential thermal analysis (DTA) are developed. Facilitated by a unique “microholes interetch and sealing (MIS)” technique, pairs of suspended thermopiles are batch fabricated in a differential form, with high-density (54 pairs) n-type/p-type single-crystal silicon thermocouples integrated within each thermopile (sample area ~0.045 mm2). The fabricated MEMS thermopile sensors exhibit outstanding power responsivity of 99.5 V/W and temperature responsivity of 27.8 mV/°C, which are more than 4 times higher than those reported for material thermal analysis. The high-responsivity MEMS DTA chips allow us to accurately measure the indium melting point at different heating rates of ~1–100 °C/s. We also perform DTA measurement of the dehydration process of CuSO4·5H2O and the crystals show three stages of losing water of crystallization before becoming anhydrous copper sulfate salt. Our high-performance, cost-effective MEMS sensing chips hold promise for rapid and accurate DTA characterization for a wide range of applications.Keywords:MEMS thermopile;differential thermal analysis;DTA;single-crystal silicon thermocouples;MIS process
研究领域:
材料科学
·
微机电系统
·
热分析技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ORGANIC PROCESS RESEARCH & DEVELOPMENT
·
2024
·
IF 3.1
Shichun Weng,Juan Zhou,Yingtao Tian,Xigui Jiang,Rong Chen,Jinyao Hu,Zichao Guo,Liping Chen,Wanghua Chen
In this article, a mixture of sulfuric acid and 50% hydrogen peroxide solution was used to produce Caro’s acid, which serves as an oxidant frequently encountered in the fine chemical industry. The chemical compatibility between 50% H2O2/H2SO4 and organic solvents is an important safety issue. The compatibility of 50% H2O2/H2SO4 and several organic solvents, including ethanol, acetonitrile, ethyl acetate, DMF, dichloroethane, DMSO, ether, and toluene, was studied by reaction calorimetry and thermal analysis techniques. It was found that the first five solvents presented good compatibility with 50% H2O2/H2SO4. DSC tests indicated that these five solvents almost did not react with 50% H2O2/H2SO4 before the onset decomposition temperature of 50% H2O2/H2SO4 (∼93.3 °C). RADEX tests showed that the reactions of 50% H2O2/H2SO4 with these solvents released heats from 800 to 1100 J g–1, and the pressure effect was obvious for these mixtures. In contrast, the last three solvents, namely, DMSO, ether, and toluene, were incompatible with 50% H2O2/H2SO4, exhibiting a significant exothermic signal at lower temperatures. Most interestingly, the mixture of DMSO and 50% H2O2/H2SO4 presented a thermal runaway phenomenon below 40 °C. The causes of this thermal runaway incident were confirmed to be the oxidation of DMSO by Caro’s acid. Reaction calorimetry tests also indicated that the oxidation rate of DMSO was fast even at 40 °C, and the adiabatic temperature rise for the oxidation of DMSO was higher than 400 K.
研究领域:
化学工程
·
安全科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）