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Influence of the post-treatment of HZSM-5 zeolite on catalytic performance for alkylation of benzene with methanol

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1777-1783页

作者： Qingtao Wang Wenwen Han Hualei Hu Jinghui Lyu Xiaolong Xu Qunfeng Zhang Hongjing Wang Xiaonian Li Institute of industrial Catalysis of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology Hangzhou 310032 China

The porous material HZSM-5 zeolite with micro-mesopore hierarchical porosity was prepared by post-treatment （combined alkali treatment and acid leaching） of parent zeolite and its catalytic performance for benzene alkylation with methanol was investigated. The effect of post-treatment on the textural properties was characterized by various techniques （including ICP-AES, XRD, nitrogen sorption isotherms, SEM, NH3-TPD, Py-IR and TG）. The results indicated that the post-treatment could modify the structural and acidic properties of HZSM-5 zeolite. In this procedure, not only additional mesopores were created by selective extraction of silicon but also the acidity was tuned. Consequently, the modified HZSM-5 zeolite showed larger external surface area with less acid sites as compared to the parent zeolite. It was found out that the modified zeolite exhibited a higher benzene conversion and xylene selectivity for alkylation of benzene with methanol as well as excellent life span of the catalyst than conventional ones. This can be explained by the facts that the presence of additional mesopores improved the diffusion property in the reactions. Furthermore, the modified zeolite showed an appropriate Bronsted acidity for effective suppression of the side reaction of methanol to olefins, thus reduced the accumulation of coke on the HZSM-5 zeolite, which was favorable for the catalyst stability. In comparison with the parent HZSM-5 zeolite, the modified zeolite by alkali treatment and acid leaching showed better performance for the benzene alkylation with methanol.

关键词： HZSM-5 zeolite Hierarchical porosity Post-treatment Benzene alkylation with methanol

Chemical, isotopic and amino acid composition of Mukundpura CM2.0(CM1) chondrite: Evidence of parent body aqueous alteration

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Geoscience Frontiers 2019年第2期10卷 495-504页

作者： N.G.Rudraswami A.K.Naik R.P.Tripathi N.BhANDari S.G.Karapurkar M.Shyam Prasad E.V.S.S.K.Babu U.V.R.Vijaya Sarathi National Institute of Oceanography (Council of Scientific and industrial research) 78 BGKT Extension Science and Spirituality research Institute National Geophysical research Institute (Council of Scientific and industrial research) Indian Institute of Chemical Technology (Council of Scientific and industrial research)

The carbonaceous chondrites are intriguing and unique in the sense that they are the only rocks that provide pristine records of the early solar nebular processes. We report here results of a detailed mineralogical, chemical, amino acid and isotopic studies of a recently observed fall at Mukundpura, near Jaipur in Rajasthan, India. Abundance of olivines in this meteorite is low and of serpentine minerals is high. FeO/SiO_2 = 1.05 in its Poorly Characterized Phases(PCP) is similar to that observed in other CM2.0 chondrites. The water content of ～9.8 wt.% is similar to that found in many other CM *** examination of matrix shows that its terrestrial weathering grade is WO but aqueous parent body alteration is high, as reflected in low abundance of identifiable chondrules and abundant remnants of chondrules(～7%). Thus, most of the chondrules formed initially have been significantly altered or dissolved by aqueous alterations on their parent bodies. The measured bulk carbon(2.3%) and nitrogen content and their isotopic(δ^(13)C =-5.5‰, δ^(15)N = 23.6%0) composition is consistent with CM2.0 classification probably bordering CM1. Several amino acids such as Alanine, Serine, Proline, Valine, Threonine,Leucine, Isoleucine, Asparagine and Histamine are present. Tyrosine and Tryptophan may occur in trace amounts which could not be precisely determined. All these data show that Mukundpura chondrite lies at the boundary of CM2.0 and CM1 type carbonaceous chondrites making it one of the most primitive chondrites.

关键词： Carbonaceous chondrite Mukundpura CM Isotope Amino acid

High halogenated nitrobenzene hydrogenation selectivity over nano Ir particles

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Chinese Journal of Chemical Engineering 2017年第3期25卷 306-312页

作者： Lei Ma Jianguo Wang Hanbing Wang Qunfeng Zhang Chunshan Lu Xiaobo He Xiaonian Li industrial Catalysis Institute of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis TechnologyHangzhou 310032China

The selective hydrogenation of halogenated nitrobenzene over noble metal catalysts(Pd, Pt, and Ir) has attracted much attention owing to its high efficiency and environmental friendliness. However, the effect of size on the catalytic performance varies among different metal catalysts. In this study, sub-nano(<3 nm) Ir and Pd particles were prepared, and their catalytic properties for hydrogenation of halogenated nitrobenzene were *** show that high selectivity(N 99%) was achieved over small Ir nanoparticles, in which the selectivity over the Pd with same size was much lower than that on Ir nanoparticles. Meanwhile, Ir and Pd have different hydrogen consumption rates and reaction rates. Density functional theory calculations showed that p-chloronitrobenzene(CNB) has different adsorption properties on Ir and Pd. The distance between oxygen(cholorine) and Ir is much shorter(longer) than that between oxygen and Pd. The reaction barriers of dechlorination of p-CNB and p-chloroaniline over different Ir models are much larger than those on Pd. Especially,lower coordination of Ir leads to larger barriers of dechlorination reaction. These theoretical results explain the difference between Ir and Pd on hydrogenation of halogenated nitrobenzene.

关键词： Halogenated nitrobenzene Selective hydrogenation Sub-nano lr Density functional

Semi-solid near-net shape rheocasting of heat treatable wrought aluminum alloys

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Transactions of Nonferrous Metals Society of China 2010年第9期20卷 1719-1724页

作者： U.A.C URLE Materials Science and Manufacturing Council for Scientific and Industrial Research

Flexibility of the CSIR-RCS, induction stirring with simultaneous air cooling process, in combination with high pressure die casting is successfully demonstrated by semi-solid rheocasting of plates performed on commercial 2024, 6082 and 7075 wrought aluminum alloys. Tensile properties were measured for the above mentioned rheocast wrought aluminum alloys in the T6 condition. The results showed that tensile properties were close to or even in some cases exceeded the minimum specifications. The yield strength and elongation of rheocast 2024-T6 exceeded the minimum requirements of the wrought alloy in the T6 condition but the ultimate tensile strength achieved only 90% of the specification because the Mg content of the starting alloy was below the commercial alloy specification. The strengths of rheocast 6082-T6 exceeded all of the wrought alloy T6 strength targets but the elongation only managed 36% of the required minimum due to porosity, caused by incipient melting during solution heat treatment, and the presence of fine intermetallie needles in the eutectic. The yield strength of rheocast 7075 exceeded the required one and the ultimate tensile strength also managed 97% of the specification; while the elongation only reached 46% of the minimum requirement also due to incipient melting porosity caused during the solution heat treatment process.

关键词： high pressure die casting (HPDC) aluminum alloys as-cast condition T6 treatment incipient melting

Development of carbon composite iron ore micropellets by using the microfines of iron ore and carbon-bearing materials in iron making

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International Journal of Minerals,Metallurgy and Materials 2015年第2期22卷 132-140页

作者： Jagannath Pal Satadal Ghorai Avimanyu Das National Metallurgical Laboratory Council of Scientific and Industrial Research

Iron ore microfines and concentrate have very limited uses in sintering processes. They are used in pelletization; however, this process is cost intensive. Furthermore, the microfines of non-coking coal and other carbon-bearing materials, e.g., blast-furnace flue dust （BFD） and coke frees, are not used extensively in the metallurgical industry because of operational difficu]ties and handling problems. In the present work, to utilize these microfines, coal composite iron oxide micropellets （2-6 mm in size） were produced through an innovative technique in which lime and molasses were used as binding materials in the micropellets. The micropellets were subsequently treated with CO2 or the industrial waste gas to induce the chemical bond formation. The results show that, at a very high carbon level of 22wt% （38wt% coal）, the cold crushing strength and abrasion index of the micropellets are 2.5-3 kg/cm2 and 5wt%-9wt%, respectively; these values indicate that the pellets are suitable for cold handling. The developed micropellets have strong potential as a heat source in smelting reduction in iron making and sintering to reduce coke breeze. The micropellets produced with BFD and coke fines （8wt%-12wt%） were used in iron ore sin- tering and were observed to reduce the coke breeze consumption by 3%-4%. The quality of the produced sinter was at par with that of the conventional blast-furnace sinter.

关键词： ironmaking microfines non-coking coal iron ore concentrates micropellets pelletizing, waste utilization

Regulation of the selective hydrogenation performance of sulfur-doped carbon-supported palladium on chloronitrobenzene

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Chinese Journal of Chemical Engineering 2023年第6期58卷 69-75页

作者： Qunfeng Zhang Bingcheng Li Yuan Zhou Deshuo Zhang Chunshan Lu Feng Feng Jinghui Lv Qingtao Wang Xiaonian Li Institute of industrial Catalysis of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis TechnologyHangzhou 310014China

The overall performance of metal catalysts can be efficiently adjusted by modifying carbon carriers with different valence sulfur *** wet impregnation technique successfully prepared carbon material carriers doped with varying sources of sulfur(Na_(2)SO_(4),NaHSO_(3),Na_(2)S·9H_(2)O).Palladium carbon catalysts doped with different sulfur precursors had been prepared with the aid of the liquid-phase reduction method of the selective hydrogenation of o-chloronitrobenzene(o-CNB)to o-chloroaniline(o-CAN).The catalyst prepared for Na_(2)S·9H_(2)O as a precursor has excellent performance,and the selectivity for o-CAN is more than 99.9%at 100%*** addition,the characterization results show that with the decrease of S valence,the electronic effect between S and Pd increases,and the outer electron shift of Pd increases,which reduces the adsorption and dissociation ability of Pd to hydrogen,resulting in excellent *** effects provided a good idea for the hydrogenation of o-CNB and a different point of view on sulfur doping in a variety of hydrogenation reactions.

关键词： Catalyst Hydrogenation Selectivity Sulfur doping Electronic effect

Bessel–Gauss photon beams with fractional order vortex propagation in weak non-Kolmogorov turbulence

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Photonics research 2016年第2期4卷 30-34页

作者： Jie Gao Yu Zhu Donglin Wang Yixin Zhang Zhengda Hu Mingjian Cheng School of Science Jiangnan University jiangsu Provincial research Center of Light industrial Optoelectronic Engineering and Technology School of Physics and Optoelectronic Engineering Xidian University

We model the effects of weak fluctuations on the probability densities and normalized powers of vortex models for the Bessel–Gauss photon beam with fractional topological charge in the paraxial non-Kolmogorov turbulence channel. We find that probability density of signal vortex models is a function of deviation from the center of the photon beam, and the farther away from the beam center it is, the smaller the probability density is. For fractional topological charge, the average probability densities of signal/crosstalk vortex modes oscillate along the beam radius except the half-integer order. As the beam waist of the photon source grows, the average probability density of signal and crosstalk vortex modes grow together. Moreover, the peak of the average probability density of crosstalk vortex modes shifts outward from the beam center as the beam waist gets larger. The results also show that the smaller index of non-Kolmogorov turbulence and the smaller generalized refractive-index structure parameter may lead to the higher average probability densities of signal vortex modes and lower average probability densities of crosstalk vortex modes. Lower-coherence radius or beam waist can give rise to less reduction of the normalized powers of the signal vortex modes, which is opposite to the normalized powers of crosstalk vortex modes.

关键词： Gauss photon beams with fractional order vortex propagation in weak non-Kolmogorov turbulence Bessel mode

Determinants of workers'attitude toward low-carbon technology adoption:empirical evidence from Chinese firms

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Chinese Journal of Population,Resources and Environment 2017年第1期15卷 80-86页

作者： Xiaoli Wang Linhai Wu School of Business Jiangnan UniversityWuxiChina Food Safety research base of jiangsu Province Jiangnan UniversityWuxiChina

As the main contribution of China's carbon emissions, low-carbon production in industrial firms becomes an inevitable choice, and industrial firm employees' attitudes on low-carbon new technology directly influence the results of low-carbon production. based on the Unified Theory of Acceptance and Use of Technology model, structural equation modeling was used to analyze the main factors influencing firm staff to accept low-carbon new technology. The study reveals that the employee's social impact, performance expectation, effort expectations and convenient conditions, and employee characteristics are all main factors affecting their acceptance attitudes on low-carbon new technology. And social influence has the largest effect on employees' acceptance attitudes toward low-carbon new technology. Accordingly, relevant policy recommendations are put forward for the future research direction.

关键词： UTAUT industrial firmemployees low-carbonnew technology usingattitude main influencingfactors SEM

White-light emission from InGaN/GaN quantum well microrings grown by selective area epitaxy

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Photonics research 2016年第1期4卷 17-20页

作者： Guofeng Yang Peng Chen Shumei Gao Guoqing Chen Rong Zhang Youdou Zheng School of Science Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and TechnologyJiangnan University School of Electronic Science and Engineering Nanjing University

Monolithic white-light-emitting diodes(white LEDs) without phosphors are demonstrated using In GaN/GaN multiple quantum wells(MQWs) grown on GaN microrings formed by selective area epitaxy on SiO_2 mask patterns. The microring structure is composed of {1-101} semi-polar facets and a(0001) c-plane, attributed to favorable surface polarity and surface energy. The white light is realized by combining short and long wavelengths of electroluminescence emissions from In GaN /GaN MQWs on the {1-101} semi-polar facets and the(0001) c-plane,respectively. The change in the emission wavelengths from each microfacet is due to the In composition variations of the MQWs. These results suggest that white emission can possibly be obtained without using phosphors by combining emission light from microstructures.

关键词： GaN In LEDs White-light emission from InGaN/GaN quantum well microrings grown by selective area epitaxy well area