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Transcriptional regulation of fleshy fruit texture

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Journal of Integrative Plant Biology 2022年第9期64卷 1649-1672页

作者： Yanna Shi Bai-Jun Li Guanqing Su Mengxue Zhang Donald Grierson Kun-Song Chen College of Agriculture and Biotechnology Zhejiang UniversityZijingang CampusHangzhou310058 China Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology Zhejiang UniversityZijingang CampusHangzhou310058 China State Agriculture Ministry Laboratory of Horticultural Plant Growth Development and Quality ImprovementZhejiang UniversityZijingang CampusHangzhou310058 China Division of Plant and Crop Sciences School of BiosciencesUniversity of NottinghamSutton Bonington CampusLoughboroughLE125RD UK

Fleshy fruit texture is a critically important quality characteristic of ripe *** is an irreversible process which operates in most fleshy fruits during ripening which,together with changes in color and taste,contributes to improvements in mouthfeel and general *** results mainly from the expression of genes encoding enzymes responsible for cell wall modifications but starch degradation and high levels of flavonoids can also contribute to texture *** fleshy fruit undergo lignification during development and post-harvest,which negatively affects eating *** softening can also lead to physical damage and infection,particularly during transport and storage which causes severe supply chain *** transcription factors(TFs)that regulate fruit texture by controlling the expression of genes involved in cell wall and starch metabolism have been *** TFs directly regulate cell wall targets,while others act as part of a broader regulatory program governing several aspects of the ripening *** this review,we focus on advances in our understanding of the transcriptional regulatory mechanisms governing fruit textural change during fruit development,ripening and *** targets for breeding and future research directions for the control of texture and quality improvement are discussed.

关键词： cell wall lignification softening texture transcription factor

Strain engineering of electro-optic constants in ferroelectric materials

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npj Computational Materials 2019年第1期5卷 1092-1096页

作者： Charles Paillard Sergei Prokhorenko Laurent Bellaiche Department of Physics and Institute for Nanoscience and Engineering University of ArkansasFayettevilleAR 72701USA

Electro-optic effects allow control of the ow of light using electric fields,and are of utmost importance for today’s information and communication technologies,such as TV displays and fiber *** search for large electro-optic constants in films is essential to the miniaturization and increased efficiency of electro-optic *** this work,we demonstrate that strain-engineering in PbTiO_(3) films allows to selectively choose which electro-optic constant to *** electro-optic constants larger than 100 pm V^(−1) are predicted,either by driving the softening of an optical phonon mode at a phase transition boundary under tensile strain,or by generating the equivalent of a negative pressure via compressive strain to obtain large piezoelectric *** particular,a r_(13) electro-optic coefficient twice as large as the one of the commonly used LiNbO_(3) electro-optic material is found here when growing PbTiO_(3) on the technologicallyimportant Si substrate.

关键词： softening constants ferroelectric

Metallurgical characteristics of armour steel welded joints used for combat vehicle construction

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Defence Technology（防务技术） 2018年第5期14卷 590-606页

作者： G.Magudeeswaran V.Balasubramanian G.Madhusudan Reddy Department of Mechanical Engineering PSNA College of Engineering and TechnologyKothandaraman NagarMuthanampatti624 622DindigulTamilnaduIndia Centre for Materials Joining&Research Department of Manufacturing EngineeringAnnamalai UniversityAnnamalai Nagar608002Tamil NaduIndia Outstanding Scientist & Associate Director Defence Metallurgical Research LaboratoryKanchanbaghHyderabad500058TelanganaIndia

Austenitic stainless steel(ASS) and High nickel steel(HNS) welding consumables are being used for welding Q&T steels, as they have higher solubility for hydrogen in austenitic phase, to avoid hydrogen induced cracking(HIC) but they are very expensive. In recent years, the developments of low hydrogen ferritic steel(LHF) consumables that contain no hygroscopic compounds are utilized for welding Q&T steels. Heat affected zone(HAZ) softening is another critical issue during welding of armour grade Q&T steels and it depends on the welding process employed and the weld thermal cycle. In this investigation an attempt has been made to study the influence of welding consumables and welding processes on metallurgical characteristics of armour grade Q&T steel joints by various metallurgical characterization procedures. Shielded metal arc welding(SMAW) and flux cored arc welding(FCAW) processes were used for making welds using ASS, LHF and HNS welding consumables. The joints fabricated by using LHF consumables offered lower degree of HAZ softening and there is no evidence of HIC in the joints fabricated using LHF consumables.

关键词： Armour grade Q&T steel Heat affected zone softening Shielded metal arc welding process Flux cored arc welding process Austenitic stainless steel Low hydrogen ferritic steel High nickel steel

Effect of freeze-thaw cycles on uniaxial mechanical properties of cohesive coarse-grained soils

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Journal of Mountain Science 2019年第9期16卷 2159-2170页

作者： QU Yong-long CHEN Guo-liang NIU Fu-jun NI Wan-kui MU Yan-hu LUO Jing College of Geology Engineering and Geomatics Chang' an University Xi'an 710054 China China Gold Group Tibet Tyrone Mining Development Co. Ltd. Tibet 850000 China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China South China Institute of Geotechnical Engineering School of Civil Engineering and Transportation South China University of Technology Guangzhou 510641 China

Freeze-thaw cycles are closely related to the slope instability in high-altitude mountain regions. In this study, cohesive coarse-grained soils were collected from a high-altitude slope in the Qinghai–Tibet Plateau to study the effect of cyclic freeze-thaw on their uniaxial mechanical properties. The soil specimens were remolded with three dry densities and three moisture contents. Then, after performing a series of freeze-thaw tests in a closed system without water supply, the soil specimens were subjected to a uniaxial compression test. The results showed that the stress-strain curves of the tested soils mainly performed as strain-softening. The softening feature intensified with the increasing dry density but weakened with an increase in freeze-thaw cycles and moisture content. The uniaxial compressive strength, resilient modulus, residual strength and softening modulus decreased considerably with the increase of freeze-thaw cycles. After more than nine freeze-thaw cycles, these four parameters tended to be stable. These parameters increased with the increase of dry density and decreased with the increasing moisture content, except for the residual strength which did not exhibit any clear variation with an increase in moisture content. The residual strength, however, generally increased with an increase in dry density. The soil structural damage caused by frozen water expansion during the freeze-thaw is the major cause for the changes in mechanical behaviors of cohesive coarse-grained soils. With results in this study, the deterioration effect of freeze-thaw cycles on the mechanical properties of soils should be considered during the slope stability analysis in high-altitude mountain regions.

关键词： Freeze thaw cycles Residual strength Resilient modulus softening modulus Uniaxial compressive strength Slope stability

HARDENING BEHAVIOUR OF STAINLESS STEEL 316 DURING FATIGUE WITH THERMAL PULSE

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Acta Metallurgica Sinica(English Letters) 1992年第4期5卷 301-304页

作者： YAN Shichun Institute of Solid State Physics,Academia Sinica,Hefei,ChinaOKUDA Shigeo MIZUBA YASHI Haka Institute of Materials Science,University of Tsukuba,Japan Inst of Solid State Physics Acad Sinica Hefei China

The softening of stainless steel 316 of non-detectable difference in magnitude induced by thermal pulse was found during fatigue with strain amplitude of 1.17×10^(-4) in temperature range of 333—*** it occurred if the measurements of fatigue with thermal pulse were performed in range of 333—***,it will become of the hardening in range of 503 —*** temperature,at which hardening of the steel induced by thermal pulse emerges in fatigue process,increases with the increasing in strain amplitudes.

关键词： fatigue hardening softening thermal pulse stainless steel

Copper matrix composites reinforced respectively with nano-SiO_2 and nano-AlN particles

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中国有色金属学会会刊：英文版 2005年第S3期15卷 132-135页

作者：吴玉程王涂根汪峰涛任榕王文芳 School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China

Two kinds of copper matrix composites reinforced respectively with nano-SiO2 and nano-AlN were prepared by powder metallurgy technique. The microstructure and properties of the composites were studied. The results show that the nano-SiO2 and nano-AlN distribution are uniform and the particulates also refine the grains. With the increase of nano-SiO2 and nano-AlN addition, the density of the both composites decreases, the resistivity increases, whereas the value of hardness reaches the maximum. softening temperature of the two kinds of composites are above 700℃ which is very high in comparison with pure copper（about 400℃）. But with the same content of nano-SiO2 and nano-AlN particles, the hardness of Cu/AlN is much higher than that of Cu/SiO2, and the resistivity of Cu/AlN is close to that of Cu/SiO2. Thus the reinforcement effect of nano-AlN is better than that of nano-SiO2.

关键词： powder metallurgy composite nano-particle resistivity hardness softening temperature

Phonon and Electron Densities of States in Amorphous Fe_(90-x)Co_(x)Zr_(10)Alloys

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Chinese Physics Letters 1995年第1期12卷 30-33页

作者： LU Zhichao XIANYU Ze LI Jizhou KANG Jian YE Chuntang LI Zhuqi SHEN Baogen Department of Physics Northeastern UniversityShenyang 110006 China Institute of Atomic Energy Beijing 102413 Institute of Physics Academia SinicaBeijing 100080

The generalized phonon density of states(PDOS)and the valence electron density of states(EDOS)of the amorphous Fe_(90-x)Co_(x)Zr_(10)(x=4,10 and 40)alloys were measured at the room temperature by inelastic neutron-scattering and x-ray photoemission spectroscopy,*** results show that the stronger the Invar effect,the softer is the PDOS in the low-energy region and the larger is the EDOS at the Fermi energy *** enhancement of electron-phonon interaction was suggested to explain the low-energy phonon softening observed in Invar alloys.

关键词： Invar softening alloys

Microstructure and properties of copper matrix composites reinforced by nano-SiC and nano-Al_2O_3 particles

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中国有色金属学会会刊：英文版 2005年第S3期15卷 136-139页

作者：汪峰涛吴玉程任榕王涂根王文芳 School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China

Copper/silicon carbide composites （Cu/SiC） and copper/alumina composites （Cu/Al2O3） were fabricated by the powder metallurgy method. The influence of reinforcement particles contents on the relevant properties of the composites and the microstructure of Cu/SiC and Cu/Al2O3 composites were studied. The reinforcement effects of nano-SiC and nano-Al2O3 particles were compared. The experimental results show that with the increase of the amount of nano-SiC and nano-Al2O3 particles, the density of the both composites decreases, the resistivity increases, whereas the hardness increases firstly and then drops. The softening temperatures of the composites are above 700℃ which is far higher than that of the pure copper, leading to the improvement of the thermal stability of the composites at high temperatures. Considering all factors, the reinforcement effects of nano-SiC are better than those of nano-Al2O3 when their contents are the same in the copper matrix.

关键词： thermal stability density copper matrix composite resistivity hardness softening temperature

Effects of hydrogen sulfide on storage quality, water mobility and cell wall metabolism of strawberry fruit

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International Journal of Agricultural and Biological Engineering 2018年第6期11卷 201-207页

作者： Huanhuan Zhi Qiqi Liu Yu Dong College of Food and Bioengineering Zhengzhou University of Light IndustryZhengzhou 450002HenanChina Department of Horticulture Oregon State UniversityMid-Columbia Agricultural Research and Extension Center3005 Experiment Station DriveHood RiverOR 97031USA

The effects of hydrogen sulfide(H_(2)S)on storage quality,cellular water distribution,and cell wall metabolism of strawberry fruit after subjected to shelf or cold storage were *** were fumigated with a range of aqueous NaHS solution(0.4-3.2 mmol/L),then stored at 20℃ for 3 d or 0℃ for 9 d.H_(2)S-treated fruit significantly maintained higher fruit firmness(FF)and titratable acidity(TA)as well as lower decay compared to the control ***,H_(2)S inhibited the loss in extractable juice(EJ)and improved storage quality that not only resulted from the suppressing of respiration rate,but also from the modification of water mobility and cell wall *** FF and EJ in H_(2)S-treated fruit were closely associated with lower exchanges of free water between vacuole and cytoplasm/free space or cell wall,water-soluble polysaccharides(WSP),and activities of cell wall-modifying ***,a potential benefit of H_(2)S on retarding softening was that the H2S can reinforce the hydrogen bonding in polysaccharides and reduce activities of cell wall-modifying enzymes,causing a stabilization of cell wall *** approval of the use of H_(2)S on foods has not yet been granted,an alternative reducing agent gas based on H2S tended to be more effective in improving strawberry quality.

关键词： hydrogen sulfide strawberry softening water mobility cell wall metabolism