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[Abstract]: The internet of things and growing demand for smaller and more advanced devices has created the problem of high heat production in electronic equipment, which greatly reduces the work performance and life of the electronic instruments. Thermal interface material (TIM) is placed in between heat generating micro-chip and the heat dissipater to conduct all the produced heat to the heat sink. The development of suitable TIM with excellent thermal conductivity (TC) in both in-plane and through-plane directions is a very important need at present. For efficient thermal management, polymer composites are potential candidates. But in general, their thermal conductivity is low compared to that of metals. The filler integration into the polymer matrix is one of the two approaches used to increase the thermal conductivity of polymer composites and is also easy to scale up for industrial production. Another way to achieve this is to change the structure of polymer chains, which fall out of the scope of this work. In this review, considering the first approach, the authors have summarized recent developments in many types of fillers with different scenarios by providing multiple cases with successful strategies to improve throughplane thermal conductivity (TPTC) (k⊥). For a better understanding of TC, a comprehensive background is presented. Several methods to improve the effective (out-plane) thermal conductivity of polymer composites and different theoretical models for the calculation of TC are also discussed. In the end, it is given a detailed conclusion that provides drawbacks of some fillers, multiple significant routes recommended by other researchers to build thermally conductive polymer composites, future aspects along with direction so that the researchers can get a guideline to design an effective polymer-based thermal interface material.

Due to their large bandgaps, multiferroic oxides, the promising candidates for overcoming the disadvantages of metal-halide perovskites as light absorbers, have so far very limited use in solar cell applications. Previous investigations demonstrate that high pressure represents an efficient tool for tuning the bandgap of multiferroic Mn3TeO6 (MTO). However, the underlying mechanism of the giant bandgap reduction discovered in MTO remains unclear, which critically prevents the design of next-generation light absorbers. In this study, we performed in situ x-ray diffraction analyses on the structure evolution of MTO upon compression and decompression, discovering a sequence of irreversible phase transitions R(3)over bar -> C2/c -> P2(1)/n. The experimental results, supported by electronic structure calculations, show the shortening of Mn-O-Mn bonding, and, to a lower extent, the decrease in connectivity of octahedra across the phase transition, explain the giant bandgap reduction of MTO. These findings will facilitate the design and synthesis of next-generation light absorbers in solar cells.

Marine flexible pipe/cables, such as umbilicals, flexible pipes and cryogenic hoses, are widely adopted in ocean engineering. The reinforcing armor layer in these pipe/cables is the main component for bearing loads, which is a typical multi-layer helically wound slender structure with different winding angles for different devices. There has been no general theoretical methodology to describe the tensile performance of these flexible pipe/cables. This paper first introduces a theory to solve the tensile mechanical behavior of a helically wound structure. Based on the curved beam theory, a solution of the tensile stress of a helically wound slender is derived. Then, the deformation mechanism of the marine flexible pipe/cables structure with different winding angles is studied. Through comparing theoretical and numerical results, the deformation characteristic of the helically wound slender structure is further explained. It is found that a sectional torsional deformation generates when the structure with a larger winding angle is under tension condition, while the sectional deformation of the structure with a smaller winding angle is mainly tension. Finally, a couple types of marine flexible pipe/cables under the tension condition are provided to analyze the mechanical performance and compare the difference between different theoretical models. The research conclusion from this paper provides a useful reference for the structural analysis and design of marine flexible pipe/cables.

The presence of extremely large negative linear compressibilities (NLC) in crystalline silver oxalate was discovered in a recent work by using first principles solid-state calculations. Although the minimum value of the NLC was found for a negative applied hydrostatic pressure, in this work the presence of NLC in this material for positive applied pressures is verified experimentally by means of high-pressure X-ray diffraction experiments performed at room temperature in the Beijing synchrotron radiation facility. The results of this study demonstrate with certainty that the compressibility of silver oxalate along [010] crystallographic direction is negative for applied pressures in the range from 0.0 to 0.85 GPa. Since the measured compressibility decreases largely as the pressure decreases, large negative values of the compressibility are expected for negative applied pressures in agreement with the results found using first principles methods. Furthermore, the analysis of the variation of the lattice parameters of the crystal structure of silver oxalate under pressure in the principal axes reference system revealed that this material also exhibits the largest negative area compressibility phenomenon found so far at zero pressure, the values of the compressibilities along two of the principal axes being − 16.7 and − 20.0 TPa−1. The negative compressibility phenomenon in silver oxalate can be rationalized in terms of a “chains of rotating parallelograms” structural model.

Content: In this study, different acid proteases, which were produced from Aspergillus and Bacillus, were applied for wet-blue bating and their properties and bating effects were observed. The results showed that the acid protease produced Aspergillus had better bating effect and higher chromium tolerance than that of produced by Bacillus. Furthermore, how the acid protease influenced wet-blue microstructure was analyzed by SEM and Micro-CT. The enzymatic properties of acid protease was studied firstly.Zeta potential analysis showed that the isoelectric point (pI) of the protease was consistent with its pH value, which was at 3.0. By particle size analysis, it found that its particle size was 700 nm. In order to obtain the functional components, the molecular weight of the acidic protease was analyzed by Polyacrylamide gel Electrophoresis (SDS-PAGE). Different molecular weight components were obtained by separating the acidic protease with Tangential Flow Filtration (TFF) Technology. The characteristics of these components were determined such as enzyme types and their proportion. Afterwards, these different molecular weight components were used for wet-blue bating. The bating effluent was collected, and then, contents of Hydroxyproline (Hyp), Hyaluronic acid (HA), Desmosine (Des) and Chondroitin sulfate (CS) were analysed, which could be directly corresponding with the degradation of different proteins in wet-blue. Therefore, by characterizing and comparing the bating effect influenced with these different molecular weight components, the functional components of protease could be identified and further be separated and purified. Based on these results, this research is helpful to the development and study of the action of acid protease in the wet-blue bating process. Take-Away: Micro-CT as a new way to characterize the microstructure of leather; Identification and Separation of Effective Components of Acid Protease； Degradation Analysis of Main Components of Wet-B

Content: With the development of China sports, researches related to sports leather should be paid attention because they usually required higher strength than commonly used leather. In this paper, we focus on the production of gymnastics leather. In gymnastics, the athlete's hand will have high intensity contact with the balance bar, so the gymnastics leather is required to have high intensity performance. At the same time, in order to comply with the ornamental function, gymnastics leather is required to be light color. In this research, glutaraldehyde was used as the main tanning agent, while acrylic polymer and synthetic were used for retanning, in order to obtain high strength, environmentally friendly white gym leather. The shrinkage temperature and mechanical properties of tanned leather were determined and analyzed to determine the suitable tanning agent. Besides, other properties including softness, gas permeability, water permeability, flexing resistance and yellowing-resistance were also measured for selecting proper production process. Therefore, gymnastics leather with ideal performance can be prepared by this method, and the leather conforms to the practical application standard. In addition, the research has guiding significance and application prospect for high strength chrome-free tanned leather. Take-Away: Aldehyde tanning agents and retanning agents, which can be used for gymnastics leather making, were evaluated and selected to achieve ideal effect of finish leather. This research is meaningful to produce not only gymnastics leather but also other sporty leather which require high strength.

Content: With the development of China sports, researches related to sports leather should be paid attention because they usually required higher strength than commonly used leather. In this paper, we focus on the production of gymnastics leather. In gymnastics, the athlete's hand will have high intensity contact with the balance bar, so the gymnastics leather is required to have high intensity performance. At the same time, in order to comply with the ornamental function, gymnastics leather is required to be light color. In this research, glutaraldehyde was used as the main tanning agent, while acrylic polymer and synthetic were used for retanning, in order to obtain high strength, environmentally friendly white gym leather. The shrinkage temperature and mechanical properties of tanned leather were determined and analyzed to determine the suitable tanning agent. Besides, other properties including softness, gas permeability, water permeability, flexing resistance and yellowing-resistance were also measured for selecting proper production process. Therefore, gymnastics leather with ideal performance can be prepared by this method, and the leather conforms to the practical application standard. In addition, the research has guiding significance and application prospect for high strength chrome-free tanned leather. Take-Away: Aldehyde tanning agents and retanning agents, which can be used for gymnastics leather making, were evaluated and selected to achieve ideal effect of finish leather. This research is meaningful to produce not only gymnastics leather but also other sporty leather which require high strength.

Content: In this study, different acid proteases, which were produced from Aspergillus and Bacillus, were applied for wet-blue bating and their properties and bating effects were observed. The results showed that the acid protease produced Aspergillus had better bating effect and higher chromium tolerance than that of produced by Bacillus. Furthermore, how the acid protease influenced wet-blue microstructure was analyzed by SEM and Micro-CT. The enzymatic properties of acid protease was studied firstly.Zeta potential analysis showed that the isoelectric point (pI) of the protease was consistent with its pH value, which was at 3.0. By particle size analysis, it found that its particle size was 700 nm. In order to obtain the functional components, the molecular weight of the acidic protease was analyzed by Polyacrylamide gel Electrophoresis (SDS-PAGE). Different molecular weight components were obtained by separating the acidic protease with Tangential Flow Filtration (TFF) Technology. The characteristics of these components were determined such as enzyme types and their proportion. Afterwards, these different molecular weight components were used for wet-blue bating. The bating effluent was collected, and then, contents of Hydroxyproline (Hyp), Hyaluronic acid (HA), Desmosine (Des) and Chondroitin sulfate (CS) were analysed, which could be directly corresponding with the degradation of different proteins in wet-blue. Therefore, by characterizing and comparing the bating effect influenced with these different molecular weight components, the functional components of protease could be identified and further be separated and purified. Based on these results, this research is helpful to the development and study of the action of acid protease in the wet-blue bating process. Take-Away: Micro-CT as a new way to characterize the microstructure of leather; Identification and Separation of Effective Components of Acid Protease； Degradation Analysis of Main Components of Wet-B

Content: In this study, different acid proteases, which were produced from Aspergillus and Bacillus, were applied for wet-blue bating and their properties and bating effects were observed. The results showed that the acid protease produced Aspergillus had better bating effect and higher chromium tolerance than that of produced by Bacillus. Furthermore, how the acid protease influenced wet-blue microstructure was analyzed by SEM and Micro-CT. The enzymatic properties of acid protease was studied firstly.Zeta potential analysis showed that the isoelectric point (pI) of the protease was consistent with its pH value, which was at 3.0. By particle size analysis, it found that its particle size was 700 nm. In order to obtain the functional components, the molecular weight of the acidic protease was analyzed by Polyacrylamide gel Electrophoresis (SDS-PAGE). Different molecular weight components were obtained by separating the acidic protease with Tangential Flow Filtration (TFF) Technology. The characteristics of these components were determined such as enzyme types and their proportion. Afterwards, these different molecular weight components were used for wet-blue bating. The bating effluent was collected, and then, contents of Hydroxyproline (Hyp), Hyaluronic acid (HA), Desmosine (Des) and Chondroitin sulfate (CS) were analysed, which could be directly corresponding with the degradation of different proteins in wet-blue. Therefore, by characterizing and comparing the bating effect influenced with these different molecular weight components, the functional components of protease could be identified and further be separated and purified. Based on these results, this research is helpful to the development and study of the action of acid protease in the wet-blue bating process. Take-Away: Micro-CT as a new way to characterize the microstructure of leather; Identification and Separation of Effective Components of Acid Protease； Degradation Analysis of Main Components of Wet-B

Content: With the development of China sports, researches related to sports leather should be paid attention because they usually required higher strength than commonly used leather. In this paper, we focus on the production of gymnastics leather. In gymnastics, the athlete's hand will have high intensity contact with the balance bar, so the gymnastics leather is required to have high intensity performance. At the same time, in order to comply with the ornamental function, gymnastics leather is required to be light color. In this research, glutaraldehyde was used as the main tanning agent, while acrylic polymer and synthetic were used for retanning, in order to obtain high strength, environmentally friendly white gym leather. The shrinkage temperature and mechanical properties of tanned leather were determined and analyzed to determine the suitable tanning agent. Besides, other properties including softness, gas permeability, water permeability, flexing resistance and yellowing-resistance were also measured for selecting proper production process. Therefore, gymnastics leather with ideal performance can be prepared by this method, and the leather conforms to the practical application standard. In addition, the research has guiding significance and application prospect for high strength chrome-free tanned leather. Take-Away: Aldehyde tanning agents and retanning agents, which can be used for gymnastics leather making, were evaluated and selected to achieve ideal effect of finish leather. This research is meaningful to produce not only gymnastics leather but also other sporty leather which require high strength.

We report an observation of a pressure-induced breakdown of the three-dimensional Dirac semimetal (3D-DSM) state in Cd3As2, evidenced by a series of in situ high-pressure synchrotron x-ray diffraction and single-crystal transport measurements. We find that Cd3As2 undergoes a structural phase transition from a metallic tetragonal phase in space group I41/acd to a semiconducting monoclinic phase in space group P21/c at critical pressure 2.57 GPa; above this pressure, an activation energy gap appears, accompanied by distinct switches in Hall resistivity slope and electron mobility. These changes of crystal symmetry and corresponding transport properties manifest the breakdown of the 3DDSM state in pressurized Cd3As2. © 2015 American Physical Society.

We report an observation of a pressure-induced breakdown of the three-dimensional Dirac semimetal (3D-DSM) state in Cd3As2, evidenced by a series of in situ high-pressure synchrotron x-ray diffraction and single-crystal transport measurements. We find that Cd3As2 undergoes a structural phase transition from a metallic tetragonal phase in space group I41/acd to a semiconducting monoclinic phase in space group P21/c at critical pressure 2.57 GPa; above this pressure, an activation energy gap appears, accompanied by distinct switches in Hall resistivity slope and electron mobility. These changes of crystal symmetry and corresponding transport properties manifest the breakdown of the 3DDSM state in pressurized Cd3As2. © 2015 American Physical Society.

We report an observation of a pressure-induced breakdown of the three-dimensional Dirac semimetal (3D-DSM) state in Cd3As2, evidenced by a series of in situ high-pressure synchrotron x-ray diffraction and single-crystal transport measurements. We find that Cd3As2 undergoes a structural phase transition from a metallic tetragonal phase in space group I41/acd to a semiconducting monoclinic phase in space group P21/c at critical pressure 2.57 GPa; above this pressure, an activation energy gap appears, accompanied by distinct switches in Hall resistivity slope and electron mobility. These changes of crystal symmetry and corresponding transport properties manifest the breakdown of the 3DDSM state in pressurized Cd3As2. © 2015 American Physical Society.

C-60 nanosheets with thicknesses in the nanometer range were synthesized by a simple method. Compared to bulk C-60, the lattice of the nanosheets is expanded by about 0.4%. In situ Raman spectroscopy and energy-dispersive x-ray diffraction under high pressures have been employed to study the structure of the nanosheets. The studies indicate that the bulk modulus of the C-60 nanosheets is significantly larger than that of bulk C-60. The C-60 cages in nanosheets can persist at pressures over 30 GPa, 3 GPa higher than for bulk C-60. These results suggest that C-60 crystals in even small size will be a potential candidate of superhard materials., Selected for Virtual Journal of Nanoscale Science and Technology vol. 16, issue 12 (Sept. 17, 2007).

by Li Yanchun., "August 2000.", Thesis (Ph.D.)--Chinese University of Hong Kong, 2002., Includes bibliographical references (p. 193-213)., Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web., Mode of access: World Wide Web., http://library.cuhk.edu.hk/record=b6073488, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

by Li Yanchun., "August 2000.", Thesis (Ph.D.)--Chinese University of Hong Kong, 2002., Includes bibliographical references (p. 193-213)., Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web., Mode of access: World Wide Web., http://library.cuhk.edu.hk/record=b6073488, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)