BIORESOURCE TECHNOLOGY
·
2014
·
IF 5.039
Yangyang Qian,Jie Zhang,Jie Wang
The pyrolysis of rice husk was conducted in a fixed-bed reactor with a sweeping nitrogen gas to investigate the effects of pressure on the pyrolytic behaviors. The release rates of main gases during the pyrolysis, the distributions of four products (char, bio-oil, water and gas), the elemental compositions of char, bio-oil and gas, and the typical compounds in bio-oil were determined. It was found that the elevation of pressure from 0.1 MPa to 5.0 MPa facilitated the dehydration and decarboxylation of bio-oil, and the bio-oils obtained under the elevated pressures had significantly less oxygen and higher calorific value than those obtained under atmospheric pressure. The former bio-oils embraced more acetic acid, phenols and guaiacols. The elevation of pressure increased the formation of CH 4 partially via the gas-phase reactions. An attempt is made in this study to clarify “the pure pressure effect” and “the combined effect with residence time”.
研究领域:
能源科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2023
·
IF 10.9
Mingxin Zhang,Cuiying Pei,Qi Wang,Yi Zhao,Changhua Li,Weizheng Cao,Shihao Zhu,Juefei Wu,Yanpeng Qi
Recently, the discovery of superconductivity with a critical temperature T c up to 80 K in Ruddlesden–Popper phases La n +1 Ni n O 3 n +1 ( n = 2) under pressure has garnered considerable attention. Up to now, the superconductivity was only observed in La 3 Ni 2 O 7 single crystal grown with the optical-image floating zone furnace under oxygen pressure. It remains to be understood the effect of chemical doping on superconducting La 3 Ni 2 O 7 as well as other Ruddlesden–Popper phases. Here, we systematically investigate the effect of external pressure and chemical doping on polycrystalline Ruddlesden–Popper phases. Our results demonstrate that the application of pressure and doping effectively tunes the transport properties of Ruddlesden–Popper phases. We find pressure-induced superconductivity up to 86 K in La 3 Ni 2 O 7 polycrystalline sample, while no signatures of superconductivity are observed in La 2 NiO 4 and La 4 Ni 3 O 10 polycrystalline samples under high pressure up to 50 GPa. Our study sheds light on the exploration of high- T c superconductivity in nickelates.
研究领域:
凝聚态物理
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2022
·
IF 4.889
Chenyang Zhao,Hongwei Zhu,Yujia Liu,Junjie Feng,Xiang Feng,Wei Xu,Zhe Yang,Bing Sun
The direct epoxidation of propylene has been a hot topic in the academic field for years. Researchers have spent extensive effort on the development of catalyst, however, only limited attention on the effect of reaction conditions, especially pressure. In this paper, we found for the first time that elevated pressure should favor the forward epoxidation reaction, it actually led to a drop of reaction rate in this system. We proposed explanation by considering the difficulty of gas molecules diffusing into and out of the micropores on the TS-1 zeolite surface. Higher pressure would inhibit the escaping of the gas molecules from the micropores and lead to carbon deposition inside the channel. To validate this hypothesis, we designed and compared catalysts with micropores blocked (BTS-1) and unblocked (TS-1) and found that the BTS-1 showed higher resistance to pressure change and significantly longer life time than the TS-1.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2020
·
IF 5.627
Yan Zhang,Xiaoyuan Zhang,Chuangchuang Cao,Jiabiao Zou,Tianyu Li,Jiuzhong Yang,Lili Ye,Yuyang Li
This work reports an experimental and kinetic modeling investigation on the flow reactor pyrolysis of iso -butylbenzene and tert -butylbenzene at 0.04 and 1 atm. Pyrolysis products were detected and identified using synchrotron vacuum ultraviolet photoionization mass spectrometry , and their mole fractions versus heating temperature were measured. High-pressure-limit and pressure-dependent rate constants of unimolecular decomposition reactions of iso -butylbenzene were calculated in this work using the same method as the theoretical calculation investigation on similar reactions of n -butylbenzene, sec -butylbenzene and tert -butylbenzene reported by Belisario-Lara et al. [ J. Phys. Chem. A , 122 (2018) 3980–4001]. Furthermore, a pyrolysis model of four butylbenzene isomers was developed from our previous models of n -butylbenzene and sec -butylbenzene and validated by the present experimental data. Modeling analysis was performed to reveal key pathways in fuel decomposition and polycyclic aromatic hydrocarbon (PAH) formation of iso -butylbenzene and tert -butylbenzene. The dominant decomposition reactions of iso -butylbenzene and tert -butylbenzene under pyrolysis conditions are benzylic C C bond dissociation reactions, while the major products in pyrolysis process are produced by β - scission reactions of primary radical products. Fuel-specific pathways are found to strongly affect the formation of PAHs, especially for indene, naphthalene and phenanthrene. Fuel isomeric effects on the pyrolysis of four butylbenzene isomers were also analyzed with special concerns on the fuel decomposition and PAH formation processes. Different sidechain structures result in different distributions of major products, while different formation pathways and concentrations of precursors lead to different formation tendency of typical PAHs.
研究领域:
化学工程
·
燃料化学
✓ 已验证
DOI
高影响因子
COMBUSTION AND FLAME
·
2019
·
IF 4.12
Dong-Xu Tian,Yue-Xi Liu,Bing-Yin Wang,Chuang-Chuang Cao,Zhong-Kai Liu,Yi-Tong Zhai,Yan Zhang,Jiu-Zhong Yang,Zhen-Yu Tian
Pyrolysis study of iso-propylbenzene (IPB) at 30 and 760 torr was carried out by using synchrotron photoionization and molecular beam mass spectrometry techniques. 0.5%IPB was diluted by helium and heated to 798–1148 K in a flow tube. Styrene was the most abundant aromatic intermediate at both pressures. Several polycyclic aromatics were only observed at 760 torr, such as 2-ethenyl-1, 4-dimethyl-benzene, fluorene, anthracene , phenanthrene, 2-methyl-anthracene and pyrene, while fulvene, 1, 3-cyclohexadiene, and 5-ethenylidene-1, 3-cyclopentadiene were only detected at 30 torr. A detail mechanism involving 306 species and 1990 reactions was developed by updating ipso-addition and unimolecular dissociation reactions of IPB as well as reactions related to styrene, indene and naphthalene . The mechanism could predict the pyrolysis of IPB and production of other intermediates well. Rate-of-production analysis shows that the formations of 2-phenethyl, 1-iso-phenylpropyl and 2-iso-phenylpropyl radicals are the main consumption reactions of IPB independent of pressure. Sensitivity analysis indicates that the unimolecular dissociation of IPB forming 2-phenethyl radical is the most significant promoting reaction at both pressures. H-abstraction reaction forming 1-iso-phenylpropyl radical tends to play a significant inhibiting effect on IPB consumption at 30 torr, while the most inhibiting reaction is self-combination of methyl radicals at 760 torr. Compared to n-propylbenzene experiments reported by Liu et al. (Combustion and Flame, 191 (2018) 53–65) and Yuan et al. (Combustion and Flame,186 (2017) 178–192.), IPB tends to produce larger quantities of benzene, styrene and indene under pyrolysis and oxidation conditions. These results will improve the understanding of the combustion and soot formation of IPB as a potential aviation surrogate fuel.
研究领域:
化学动力学
·
燃烧科学
✓ 已验证
DOI
高影响因子
Cell Reports Physical Science
·
2023
·
IF 8.9
Huangjie Lu,Zhaofa Zheng,Jie Qiu,Yu-Chang Hou,Huiliang Hou,Ting Wen,Xiaofeng Guo,Qing-Jiang Pan,Yonggang Wang,Jian-Qiang Wang,Jian Lin
Developing photochromic materials and acquiring fundamental knowledge of their underlying photophysics is significant in diverse fields, including optoelectronics, sensing, catalysis, data storage, and more. Herein, we demonstrate how the photochromism of coordination polymers can be realized by creating lanthanide contraction, whose role in directing photophysics has previously remained elusive. Integrating different lanthanide cations and a π-electron conjugated terpyridine-based ligand (tpbz – ) affords nine isomorphous one-dimensional lanthanide coordination polymers of the formula Ln(tpbz) 3 (where the lanthanide [Ln] ranges from europium to lutetium). The decreasing ionic radii of the Ln centers across the 4f block result in increasingly condensed packing of the metal-ligand assembly. This trend affords a spectrally selective photochromic response in the lutetium polymer Lu(tpbz) 3 , contrasting sharply with the nonphotochromic earlier analogs. Experimental and theoretical investigations reveal that the chromism can be attributed to the progressively enhanced intermolecular charge transfer of adjacent tpbz – moieties induced by either Ln contraction or external pressure.
研究领域:
材料科学
·
光物理学
·
化学
✓ 已验证
DOI
高影响因子
NATURE
·
2024
·Vol. 631
·期 8021
·531-536
·
IF 50.5
Zhu Yinghao,Peng Di,Zhang Enkang,Pan Bingying,Chen Xu,Chen Lixing,Ren Huifen,Liu Feiyang,Hao Yiqing,Li Nana,Xing Zhenfang,Lan Fujun,Han Jiyuan,Wang Junjie,Jia Donghan,Wo Hongliang,Gu Yiqing,Gu Yimeng,Ji Li,Wang Wenbin,Gou Huiyang,Shen Yao,Ying Tianping,Chen Xiaolong,Yang Wenge,Cao Huibo,Zheng Changlin,Zeng Qiaoshi,Guo Jian-gang,Zhao Jun
The pursuit of discovering new high-temperature superconductors that diverge from the copper-based model 1 , 2 , 3 has profound implications for explaining mechanisms behind superconductivity and may also enable new applications 4 , 5 , 6 , 7 , 8 . Here our investigation shows that the application of pressure effectively suppresses the spin–charge order in trilayer nickelate La 4 Ni 3 O 10− δ single crystals, leading to the emergence of superconductivity with a maximum critical temperature ( T c ) of around 30 K at 69.0 GPa. The d.c. susceptibility measurements confirm a substantial diamagnetic response below T c , indicating the presence of bulk superconductivity with a volume fraction exceeding 80%. In the normal state, we observe a strange metal behaviour, characterized by a linear temperature-dependent resistance extending up to 300 K. Furthermore, the layer-dependent superconductivity observed hints at a unique interlayer coupling mechanism specific to nickelates, setting them apart from cuprates in this regard. Our findings provide crucial insights into the fundamental mechanisms underpinning superconductivity, while also introducing a new material platform to explore the intricate interplay between the spin–charge order, flat band structures, interlayer coupling, strange metal behaviour and high-temperature superconductivity.
研究领域:
物理学
·
材料科学
✓ 已验证
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Deng Zhao,Xuetong Li,Wei Luo,Qingxin Li,Wenming Han,Huashan Wang,Hua Liu,Hui Liu,Shuai Guo,Jiajing Kou
The gasification of phenol can be accelerated by the use of supercritical water (SCW) during the reaction, but continuously increasing the SCW pressure past a certain threshold will eventually inhibit this reaction. This paper reports the first use of metadynamics simulations to explain this mechanism by describing the waterline structure and fine structure of the phenol dimer better than reactive force field (ReaxFF). Discontinuous experiments showed that when increasing the SCW pressure from 23.5 MPa to 25.5 MPa, the reaction rate increased by 31 %, and when the pressure continued to increase to 29.5 MPa, the reaction rate decreased by 87 %, and then the reaction rate increased again at very high pressure. The simulation of single phenol molecule showed that the underlying reason that supercritical water promoted the gasification of phenol was the formation of waterline structures, which accelerated H transfer, disrupted of C structures, and polarized water molecules, thereby accelerating the gasification reaction. Multiple phenol molecules simulations and experiments showed that excess pressure drove dimer formation, the dimer also reduced the active sites of the benzene ring. A higher pressure formed a more complex dimer structure, which required more energy to destroy. Same law as the experiment, when the density of the supercritical water state in which the multiple phenol molecules is located rises from 0.706 g/cm 3 to 0.868 g/cm 3 , the energy barrier to reach the transition state rises 94 kacl/mol. Metadynamics simulations allowed for a more detailed description of the state of the SCW and its oxidation mechanism, thus describing how the environment influenced the reaction mechanism.
研究领域:
化学工程
·
计算化学
✓ 已验证
产品关联
DOI
高影响因子
npj Quantum Materials
·
2020
·Vol. 5
·期 1
·1-8
·
IF 6.562
Cheng Erjian,Xia Wei,Shi Xianbiao,Yu Zhenhai,Wang Lin,Yan Limin,Peets Darren C.,Zhu Chuchu,Su Hao,Zhang Yong,Dai Dongzhe,Wang Xia,Zou Zhiqiang,Yu Na,Kou Xufeng,Yang Wenge,Zhao Weiwei,Guo Yanfeng,Li Shiyan
Topological nodal-line semimetals (TNLSMs) are materials whose conduction and valence bands cross each other, meeting a topologically protected closed loop rather than discrete points in the Brillouin zone (BZ). The anticipated properties for TNLSMs, include drumhead-like nearly flat surface states, unique Landau energy levels, special collective modes, long-range Coulomb interactions, or the possibility of realizing high-temperature superconductivity. Recently, SrAs 3 has been theoretically proposed and then experimentally confirmed to be a TNLSM. Here, we report high-pressure experiments on SrAs 3 , identifying a Lifshitz transition below 1 GPa and a superconducting transition accompanied by a structural phase transition above 20 GPa. A topological crystalline insulator (TCI) state is revealed by means of density functional theory (DFT) calculations on the emergent high-pressure phase. As the counterpart of topological insulators, TCIs possess metallic boundary states protected by crystal symmetry, rather than time reversal. In consideration of topological surface states (TSSs) and helical spin texture observed in the high-pressure state of SrAs 3 , the superconducting state may be induced in the surface states, and is most likely topologically nontrivial, making pressurized SrAs 3 a strong candidate for topological superconductor.
研究领域:
凝聚态物理学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2020
·
IF 4.189
Pengfei Shen,Douglas A. Blom,Sen Shao,Jinhyuk Choi,Thomas Vogt,Yanming Ma,Lin Wang,Yongjae Lee
Tuning of physical properties opens up opportunities for new applications of known materials, as the changes induced by hydrostatic pressures can sometimes be mimicked by chemical pressures created by appropriate substitutions or at the interfaces. In contrast to bulk In2O3, where photoluminescence (PL) is reduced by pressure, pressure-induced photoluminescence enhancement (PIPE) by a factor of 4.4 was found in In2O3 nanowires (NWs). Density functional theory (DFT) calculations indicate that PIPE in NWs may be ascribed to the orbital overlap between oxygen-induced defect levels and the conduction band minimum (CBM), which does not occur in bulk In2O3. Both the PL intensity and absorption spectra of In2O3 NWs point to a discontinuity near 16 GPa. Rietveld refinements indicate that these changes in optical properties are concomitant with structural distortions, leading to strained bonds in the InO6 octahedra and trigonal prisms. The optical transmittance (T) of the NWs after compression up to 5.29 GPa is reversible after the pressure release. However, NWs compressed to 12.27 GPa and then reinvestigated at ambient pressure reveal that T increases. At compressions of up to 24.85 GPa, T at ambient conditions was enhanced by 8.29%. Synchrotron X-ray scattering and Raman spectra of NWs compressed to 24.85 GPa indicate that a local distortion of the cubic bixbyite structure is present at ambient conditions. This study establishes a correlation between changes in PL and T of In2O3 NWs and local structural distortions resulting in oxygen-induced defects, which overlap with the conduction band states as suggested by DFT calculations. Our work suggests that the optical properties of ternary metallic oxide NWs with bixbyite structure might be improved by appropriate substitutions.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·Vol. 48
·期 20
·30517-30523
·
IF 5.532
Yang Shi,Zhangyi Huang,Jingjing Chen,Mao Deng,Mingyu Su,Jianqi Qi,Jun Wang,Haomin Wang
High-density (∼99.34%), fine-grained (∼685 nm) ZnO ceramic was successfully fabricated by the high-pressure cold sintering. The influences of solvent (liquid phase) fraction and the applied pressure on densification in this process have been carefully studied. The excess solvent can result in grain refinement, but impedes the densification of ceramic. Significantly, the role of pressure is unlike that in the traditional pressure-assisted sintering, which can improve the densification and inhibit grain growth. There is a critical pressure (∼1 GPa) that can be associated with the transition of recrystallization from heterogeneous nucleation to homogeneous nucleation . When the pressure is lower than this critical value, the applied pressure can improve densification, but cannot inhibit grain growth. Above the critical value, the densification is dramatically weakened and many small crystals in the interstitial space between grains can be found.
研究领域:
材料科学
·
陶瓷学
·
固态化学
·
纳米材料
·
生物医学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Shuangchun Jiang,He Tao,Yingjuan Shao,Yao Fu,Wenqi Zhong
The pressurization can significantly enhance the thermochemical energy storage performance of Ca-based materials. In this study, detailed experimental investigations were conducted in both fixed bed and fluidized bed on the performance of TiO 2 modified Ca-based materials ranged from 700 °C to 900 °C under pressurized conditions (0.1 MPa to 0.8 MPa) from powder to pellet, including the influence of inert dopants on the properties of CaO powder, the optimization of biomass pore-former agents' selection and the enhancement of pressurized fluidization states on the performance of pelletized materials. The findings indicated that the pressure intensity has a positive correlation with the energy storage density and cyclic stability of TiO 2 modified Ca-based materials. The results demonstrated that the properties of CaO powder intensified with the pressure and the energy storage density was increased by 31.4 % with 5 % TiO 2 doped at 0.8 MPa. And the energy storage performance of the pelletized CaO-5TiO 2 with 10 % bagasse added was also significantly improved at a higher-pressure condition. The energy storage performance of the determined 10B-CaO-5TiO 2 pellet under fluidization conditions at 0.8 MPa was 38.9 % higher than that of atmospheric pressure after 10 cycles. As the carbonation pressure increased, the average grain size of CaO exhibited a decline of 7.0 %, a slighter sintering and deeper reaction region were observed into the determined pellet. Furthermore, the specific surface area and pore volumes of the 10B-CaO-5TiO 2 pellets under high carbonation pressure were 382.8 % and 460.0 % higher than that of atmospheric pressure in the fluidized bed, respectively.
研究领域:
材料科学
·
能源化学
·
化学工程
·
多相催化
·
储能技术
✓ 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）