Search

Your search keyword '"Zhang, Daliang"' showing total 453 results
Start Over Author "Zhang, Daliang"
453 results on '"Zhang, Daliang"'

107. InGaN/GaN nanowires epitaxy on large-area MoS2 for high-performance light-emitters

Author

Zhao, Chao, primary, Ng, Tien Khee, additional, Tseng, Chien-Chih, additional, Li, Jun, additional, Shi, Yumeng, additional, Wei, Nini, additional, Zhang, Daliang, additional, Consiglio, Giuseppe Bernardo, additional, Prabaswara, Aditya, additional, Alhamoud, Abdullah Ali, additional, Albadri, Abdulrahman M., additional, Alyamani, Ahmed Y., additional, Zhang, X. X., additional, Li, Lain-Jong, additional, and Ooi, Boon S., additional

Published
2017
Full Text
View/download PDF

108. Anisotropic Self-Assembly of Organic–Inorganic Hybrid Microtoroids

Author

Al-Rehili, Safa’a, primary, Fhayli, Karim, additional, Hammami, Mohamed Amen, additional, Moosa, Basem, additional, Patil, Sachin, additional, Zhang, Daliang, additional, Alharbi, Ohoud, additional, Hedhili, Mohamed Nejib, additional, Möhwald, Helmuth, additional, and Khashab, Niveen M., additional

Published
2016
Full Text
View/download PDF

109. Investigating the Origin of Enhanced C2+Selectivity in Oxide-/Hydroxide-Derived Copper Electrodes during CO2Electroreduction

Author

Lei, Qiong, Zhu, Hui, Song, Kepeng, Wei, Nini, Liu, Lingmei, Zhang, Daliang, Yin, Jun, Dong, Xinglong, Yao, Kexin, Wang, Ning, Li, Xinghua, Davaasuren, Bambar, Wang, Jianjian, and Han, Yu

Abstract

Oxide-/hydroxide-derived copper electrodes exhibit excellent selectivity toward C2+products during the electrocatalytic CO2reduction reaction (CO2RR). However, the origin of such enhanced selectivity remains controversial. Here, we prepared two Cu-based electrodes with mixed oxidation states, namely, HQ-Cu (containing Cu, Cu2O, CuO) and AN-Cu (containing Cu, Cu(OH)2). We extracted an ultrathin specimen from the electrodes using a focused ion beam to investigate the distribution and evolution of various Cu species by electron microscopy and electron energy loss spectroscopy. We found that at the steady stage of the CO2RR, the electrodes have all been reduced to Cu0, regardless of the initial states, suggesting that the high C2+selectivities are not associated with specific oxidation states of Cu. We verified this conclusion by control experiments in which HQ-Cu and AN-Cu were pretreated to fully reduce oxides/hydroxides to Cu0, and the pretreated electrodes showed even higher C2+selectivity compared with their unpretreated counterparts. We observed that the oxide/hydroxide crystals in HQ-Cu and AN-Cu were fragmented into nanosized irregular Cu grains under the applied negative potentials. Such a fragmentation process, which is the consequence of an oxidation–reduction cycle and does not occur in electropolished Cu, not only built an intricate network of grain boundaries but also exposed a variety of high-index facets. These two features greatly facilitated the C–C coupling, thus accounting for the enhanced C2+selectivity. Our work demonstrates that the use of advanced characterization techniques enables investigating the structural and chemical states of electrodes in unprecedented detail to gain new insights into a widely studied system.

Published
2020
Full Text
View/download PDF

112. Hierarchial Zeolites: Beyond Creation of Mesoporosity: The Advantages of Polymer‐Based Dual‐Function Templates for Fabricating Hierarchical Zeolites (Adv. Funct. Mater. 12/2016)

Author

Tian, Qiwei, primary, Liu, Zhaohui, additional, Zhu, Yihan, additional, Dong, Xinglong, additional, Saih, Youssef, additional, Basset, Jean‐Marie, additional, Sun, Miao, additional, Xu, Wei, additional, Zhu, Liangkui, additional, Zhang, Daliang, additional, Huang, Jianfeng, additional, Meng, Xiangju, additional, Xiao, Feng‐Shou, additional, and Han, Yu, additional

Published
2016
Full Text
View/download PDF

113. Beyond Creation of Mesoporosity: The Advantages of Polymer‐Based Dual‐Function Templates for Fabricating Hierarchical Zeolites

Author

Tian, Qiwei, primary, Liu, Zhaohui, additional, Zhu, Yihan, additional, Dong, Xinglong, additional, Saih, Youssef, additional, Basset, Jean‐Marie, additional, Sun, Miao, additional, Xu, Wei, additional, Zhu, Liangkui, additional, Zhang, Daliang, additional, Huang, Jianfeng, additional, Meng, Xiangju, additional, Xiao, Feng‐Shou, additional, and Han, Yu, additional

Published
2016
Full Text
View/download PDF

122. Method of achieving a wide field-of-view head-mounted display with small distortion

Author

Lv Weizhen, Wei Zhonglun, Fei He, Yang Jianming, Liu Weiqi, Kang Yusi, and Zhang Daliang

Subjects
Catadioptric system, Optics, Offset (computer science), Computer science, Distortion problem, business.industry, Image quality, Optical head-mounted display, Virtual reality, business, Wide field, Ellipsoid, Atomic and Molecular Physics, and Optics
Abstract

We present a method of achieving a wide-angle, lightweight, optical see-through, distortion-free head-mounted display (HMD) by using two similar ellipsoids. An HMD that achieves a single channel field-of-view (FOV) of 120°×120° with a 6 mm eye box and a total binocular FOV of 160°×120° with an 80° field overlap is designed as an example. This method can solve the complex tiling problem and the distortion problem of other catadioptric structures. This structure is used to offset distortion and correct aberrations.

Published
2013

124. Design of wide field-of-view head-mounted display optical system with double freeform surfaces

Author

Zhu Xiuqing, Zhang Daliang, Jiang Guohua, Yang Jianming, Liu Weiqi, and Meng Xiangxiang

Subjects
Physics, business.industry, Exit pupil, Image quality, Distortion (optics), Aerospace Engineering, Optical head-mounted display, Wide field, Ellipsoid, Atomic and Molecular Physics, and Optics, Tilt (optics), Optics, Space and Planetary Science, Vertical direction, Electrical and Electronic Engineering, business
Abstract

Field-of-view(FOV) is the key performance indicator to evaluate a head-mounted display (HMD) in areas such as virtual reality. In order to overcome the difficulties of a sharp increase of optical system aberrations with the increased FOV, a wide FOV HMD optical system with double freeform surfaces was proposed. First, the principles of the double ellipsoid HMD which could achieve large FOV and low distortion were analyzed, and the reason of the aberration correction limitations of the double ellipsoid HMD was pointed out. Then wide FOV HMD optical system with double freeform mirrors was proposed. Two free-form mirrors were used by the new optical system which were symmetrical in vertical direction and asymmetrical in horizontal direction to correct off-axis aberrations brought by increasing FOV. The FOV of the new optical system was 106.3(H)80(V). The maximum relative distortion is 6.97%. The exit pupil diameter was 8 mm and the eye clearance distance was 19 mm. Through tilt outside 8 the binocular FOV was 122.3(H)80(V) and the binocular overlapped FOV was 90.3(H)80(V). The IPD is adjustable within 55-71 mm. The analysis of optical performance indicates that image quality is greatly improved, and the relative distortion and FOV can meet the application requirements of the virtual reality.

Published
2016

126. Design of off-axis three-mirror optical system with wide field of view based on transfer matrix

Author

Wang Yunqi, Meng Xiangxiang, Kang Yusi, Liu Weiqi, Wei Zhonglun, and Zhang Daliang

Subjects
Computer science, business.industry, Aerospace Engineering, Field of view, Transfer matrix, Atomic and Molecular Physics, and Optics, F-number, Optics, Space and Planetary Science, Systems design, Rectangle, Electrical and Electronic Engineering, Focus (optics), Secondary mirror, business, Zemax
Abstract

To the problem that off-axis three-mirror optical system has narrow field and complicating initial structure solving process, a method by using optical transfer matrix to solve initial structure was proposed, the focus length and rear cut-off distance of three-mirror system was deduced, then an initial structure parameter of three-mirror system with aperture stop on secondary mirror was given. High order aspheric surface was used to increase system design variance, and making off-axial optimization design to coaxial system based on optical design software ZEMAX, finally got an off-axis three-mirror optical system with wide rectangle field of view 172, focus length of 1 440 mm, F number of 4.8. The system has three high order aspheric optical elements, it can satisfy the requirement of high resolution and large field, the MTF is more than 0.6 at 50 lp/mm, approaches to the diffraction limitation. The designed result shows that the system can be used in space of imaging system with Timed Delay and Integrated Charge-couple Device(TDI-CCD), can expand the ground coverage of system obviously, and achieves high information retrieval efficiency.

Published
2016

130. Metal–Organic Framework Based upon the Synergy of a Brønsted Acid Framework and Lewis Acid Centers as a Highly Efficient Heterogeneous Catalyst for Fixed-Bed Reactions

Author

Li, Baiyan, primary, Leng, Kunyue, additional, Zhang, Yiming, additional, Dynes, James J., additional, Wang, Jian, additional, Hu, Yongfeng, additional, Ma, Dingxuan, additional, Shi, Zhan, additional, Zhu, Liangkui, additional, Zhang, Daliang, additional, Sun, Yinyong, additional, Chrzanowski, Matthew, additional, and Ma, Shengqian, additional

Published
2015
Full Text
View/download PDF

134. ITQ-37 a chiral zeolite framework following the SrSi2 net and containing 30-ring extra-large gyroidal channels

Author

Sun, Junliang, Bonneau, Charlotte, Cantin Sanz, Angel, Corma Canós, Avelino, Díaz Cabañas, Mª José, Moliner Marin, Manuel, Zhang, Daliang, Li, Mingrun, and Zou, Xiaodong

Subjects
QUIMICA ORGANICA
Abstract

[EN] The synthesis of crystalline molecular sieves with pore dimensions that fill the gap between microporous and mesoporous materials is a matter of fundamental and industrial interest(1-3). The preparation of zeolitic materials with extralarge pores and chiral frameworks would permit many new applications. Two important steps in this direction include the synthesis(4) of ITQ-33, a stable zeolite with 18 x 10 x 10 ring windows, and the synthesis(5) of SU-32, which has an intrinsically chiral zeolite structure and where each crystal exhibits only one handedness. Here we present a germanosilicate zeolite (ITQ-37) with extralarge 30-ring windows. Its structure was determined by combining selected area electron diffraction ( SAED) and powder X-ray diffraction (PXRD) in a charge-flipping algorithm(6). The framework follows the SrSi2 (srs) minimal net(7) and forms two unique cavities, each of which is connected to three other cavities to form a gyroidal channel system. These cavities comprise the enantiomorphous srs net of the framework. ITQ-37 is the first chiral zeolite with one single gyroidal channel. It has the lowest framework density (10.3 T atoms per 1,000 angstrom(3)) of all existing 4-coordinated crystalline oxide frameworks, and the pore volume of the corresponding silica polymorph would be 0.38 cm(3) g(-1)., This project is supported by the CICYT ( Project MAT 2006-14274-C02-01 and Prometeo 2008 GV), the Swedish Research Council (VR) and the Swedish Governmental Agency for Innovation Systems (VINNOVA). J.S. and C. B. are supported by post-doctoral grants from the Carl-Trygger and Wenner-Gren foundations respectively. M. M. thanks ITQ for a scholarship.

Published
2009

141. Highly Mesoporous Single-Crystalline Zeolite Beta Synthesized Using a Nonsurfactant Cationic Polymer as a Dual-Function Template

Author

Zhu, Jie, primary, Zhu, Yihan, additional, Zhu, Liangkui, additional, Rigutto, Marcello, additional, van der Made, Alexander, additional, Yang, Chengguang, additional, Pan, Shuxiang, additional, Wang, Liang, additional, Zhu, Longfeng, additional, Jin, Yinying, additional, Sun, Qi, additional, Wu, Qinming, additional, Meng, Xiangju, additional, Zhang, Daliang, additional, Han, Yu, additional, Li, Jixue, additional, Chu, Yueying, additional, Zheng, Anmin, additional, Qiu, Shilun, additional, Zheng, Xiaoming, additional, and Xiao, Feng-Shou, additional

Published
2014
Full Text
View/download PDF

146. Synthesis and Visible-light Photocatalytic Performance of C-doped Nb2O5with High Surface Area

Author

Ding, Shuang, Wang, Runwei, Zhang, Panpan, Kang, Bonan, Zhang, Daliang, Zhang, Zongtao, and Qiu, Shilun

Abstract

C-doped Nb2O5with abundant mesopores has been successfully synthesized through a facile solvothermal synthetic strategy followed by calcination treatment. The resulting C-doped Nb2O5displayed the highest BET surface area(345 m2/g) and large mesopore size(ca. 4.2 nm), capable of offering more accessible active sites as well as faster mass transfer for catalysis. Besides, the doping of C(2.21%, molar fraction) at the O sites in Nb2O5lattice greatly enhanced visible-light response by lowering the band gap, thereby making the material a photocatalyst under visible-light irradiation. Typically, the C-doped Nb2O5exhibited a high H2 evolution rate of ca. 39.10 μmol·g–1·h–1and also degraded RhB dye completely after 30 min of visible light exposure, which turned out to be much better than Degussa P25 and pure Nb2O5catalysts.

Published
2018
Full Text
View/download PDF

147. Structure and catalytic properties of the most complex intergrown zeolite ITQ-39 determined by electron crystallography

Author

Willhammar, Tom, Sun, Junliang, Wan, Wei, Oleynikov, Peter, Zhang, Daliang, Zou, Xiaodong, Moliner, Manuel, Gonzalez, Jorge, Martínez, Christina, Rey, Fernando, Corma, Avelino, Willhammar, Tom, Sun, Junliang, Wan, Wei, Oleynikov, Peter, Zhang, Daliang, Zou, Xiaodong, Moliner, Manuel, Gonzalez, Jorge, Martínez, Christina, Rey, Fernando, and Corma, Avelino

Abstract

Porous materials such as zeolites contain well-defined pores in molecular dimensions and have important industrial applications in catalysis, sorption and separation. Aluminosilicates with intersecting 10- and 12-ring channels are particularly interesting as selective catalysts. Many porous materials, especially zeolites, form only nanosized powders and some are intergrowths of different structures, making structure determination very challenging. Here, we report the atomic structures of an aluminosilicate zeolite family, ITQ-39, solved from nanocrystals only a few unit cells in size by electron crystallography. ITQ-39 is an intergrowth of three different polymorphs, built from the same layer but with different stacking sequences. ITQ-39 contains stacking faults and twinning with nano-sized domains, being the most complex zeolite ever solved. The unique structure of ITQ-39, with a three-dimensional intersecting pairwise 12-ring and 10-ring pore system, makes it a promising catalyst for converting naphtha into diesel fuel, a process of emerging interest for the petrochemical industry.

Published
2012
Full Text
View/download PDF

148. Controlled Synthesis of the Tricontinuous Mesoporous Material IBN-9 and Its Carbon and Platinum Derivatives

Author

Zhao, Yunfeng, Zhang, Daliang, Zhao, Lan, Wang, Guangchao, Zhu, Yihan, Cairns, Amy, Sun, Junliang, Zou, Xiaodong, Han, Yu, Zhao, Yunfeng, Zhang, Daliang, Zhao, Lan, Wang, Guangchao, Zhu, Yihan, Cairns, Amy, Sun, Junliang, Zou, Xiaodong, and Han, Yu

Abstract

Controlled synthesis of mesoporous materials with ultracomplicated pore configurations is of great importance for both fundamental research of nanostructures and the development of novel applications. IBN-9, which is the only tricontinuous mesoporous silica with three sets of interpenetrating three-dimensional channel systems, appears to be an excellent model mesophase for such study. The extensive study of synthesis space diagrams proves mesophase transition among the cylindrical MCM-41, tricontinuous IBN-9 and bicontinuous MCM-48, and also allows a more precise control of phase-pure synthesis. On the other hand, rational design of structure-directing agents offers a possibility to extend the synthesis conditions of IBN-9, as well as tailor its pore size. Moreover, an unprecedented helical,-structure consisting of twisted 3-fold interwoven mesoporous channels is reported here for the first time. The unique tricontinuous mesostructure of IBN-9 has been well-replicated by other functional materials (e.g., carbon and platinum) via a hard-templating synthesis route. The obtained carbon material possesses large surface area (similar to 1900 m(2)/g), high pore volume (1.56 cm(3)/g), and remarkable gas adsorption capability at both cryogenic temperatures and room temperature. The platinum material has an ordered mesostructure composed of highly oriented nanocrystals., authorCount :9

Published
2011
Full Text
View/download PDF

149. 3D Electron crystallography : Real space reconstruction and reciprocal space tomography

Author

Zhang, Daliang and Zhang, Daliang

Abstract

Electron crystallography is an important technique for studying micro- and nano-sized materials. It has two important advantages over X-ray crystallography for structural studies: 1) crystals millions of times smaller than those needed for X-ray diffraction can be studied; 2) it is possible to; focus the electrons to form an image. The local atomic arrangement can be seen directly by high-resolution transmission electron microscopy (HRTEM). The crystallographic structure factor phases, which are lost in recording diffraction patterns, are present in HRTEM images and can be determined experimentally. The main disadvantages of electron crystallography compared to X-ray diffraction are that the data are difficult to collect, often incomplete and suffer from dynamic scattering. New methods need to be developed to overcome these problems. In this work, structure determination of several unique and complex porous materials including zeolites and mesoporous silica is demonstrated. None of the structures of these materials could be solved by X-ray crystallography. New techniques are also developed in order to overcome the disadvantages of electron crystallography. The new techniques include a digital sampling method for collecting precession electron diffraction data and a rotation method for automatic collection of complete 3D electron diffraction data. A number of practical issues concerning data collection and data processing are described and the data quality is analysed., At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Submitted.

Published
2010

150. Two New Layered Oxohalides in the System Cu-Yb-Te-O-Cl

Author

Zhang, Daliang, Johnsson, Mats, Kremer, R.K., Zhang, Daliang, Johnsson, Mats, and Kremer, R.K.

Abstract

Two complex lanthanide(III) transition metal(II) tellurium(IV) oxyhalides, Cu3Yb2(TeO3)4Cl4 and Cu3Yb3(TeO3)4Cl6 have been synthesized and the crystal structures were determined by single-crystal X-ray diffraction. Both compounds are layered with only weak connections in between the layers. The layers are made up of [YbO8], [TeO3] and [CuOxCly] polyhedra. In both compounds the strong Lewis acid cations Yb3+ and Te4+ only form bonds to oxygen while Cu2+ form bonds to both oxygen and chlorine. This leads the Cl− ions to be expelled from the bonding volumes of the crystal structures and protrude from the layers. Magnetic susceptibility measurements were performed on a powder sample of Cu3Yb2(TeO3)4Cl4. The Curie–Weiss law found at low temperatures indicates a Curie–Weiss temperature of ca. −5(1) K. However, indication for long-range magnetic ordering could not be observed down to 1.87 K. The two new phases are to the best of our knowledge the first containing all three of Cu, Yb and Te., 3

Published
2010
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results