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Growth and Holographic Storage Properties of Sc, Fe Co-Doped Lithium Niobate Crystals

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Journal of Rare Earths 2007年第6期25卷 775-778页

作者：郑威张乃东雷清泉 College of Materials science and Engineering Harbin University of Science and Technology College of Environmental science and Engineering Dalian Marine University College of Electrician Engineering Harbin University of Science and Technology

The holographic storage properties of Fe （0.03% （mass fraction） Fe2O3）：LiNbO3 doped with Sc at different levels （0, 1%, 2%, 3%） were investigated. The Sc threshold concentration in Fe：LiNbO3 was implied to be about 3% （mole fraction） because O-H vibration absorption peak of Sc （3%）：Fe：LiNbO3 was at 3508 cm^-1, compared with 3484 cm^-1 of crystals with lower Sc doping level. Sc（3%）：Fe：LiNbO3 exhibited higher optical damage resistance ability. The threshold intensity （wavelength 488 nm） of Sc （3%）：Fe：LiNbO3 was 2.2 ×10^2 W ·cm^-2, two orders of masnitude higher than that of Fe：LiNbO3. Holographic storage properties of the crystals were determined in an extraordinary polarized laser of wavelength 632.8 nm by a two-wave coupling method. It was found that in terms of holographic storage properties, the optimal doping concentration of Sc was 2% （mole fraction） among this crystal series.

关键词： lithium niobate crystal Sc doping holographic storage properties rare earths

Introduction of rare-earth element Sc in alloy design to modify wear features of dual-phase high-entropy alloy

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Rare Metals 2024年第2期43卷 817-828页

作者： Hao Ren Rui-Run Chen Xue-Feng Gao Tong Liu Gang Qin Yu-Lung Chiu Shi-Ping Wu Jing-Jie Guo Guo National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin150001China School of Metallurgy and Materials University of BirminghamBirminghamB152TTUK

Tailoring the alloy composition,which induces the hard secondary phase to increase hardness and strength to improve the wear features,is a feasible approach for developing wear-resistant metal ***,a group of(AlCoCrFeNi)_(100–x)Sc_(x)(x=0–2.0,at%)high-entropy alloys(HEAs)are designed and the phase compositions and wear behaviors are ***-doped HEA series contain the primary body-centered cubic(BCC)and eutectic phases,in which the eutectic phase is composed of the alternately grown BCC and Laves *** addition promotes the diffusion of Ni atoms from BCC phase to form the Sc-rich Laves phase at the grain *** hardness increases due to solid solution strengthening and second phase *** the second phase strengthening plays a more significant role relative to solid solution *** phase and the oxides caused by wear heating prevent the direct contact between friction pair and HEAs,thus inducing a decreased wear rate from 6.82×10^(−5) to 3.47×10^(−5)m^(3)·N^(−1)·m^(−1).Moreover,the wear mechanism changes from adhesive wear,abrasive wear and oxidative wear to abrasive wear and oxidative wear.

关键词： High entropy alloy(HEA) Laves phase Hardness Wear mechanism

Synthesis and Crystal Structure of a Dinuclear Cobalt(II) Complex [Co_2(1H-benzimidazole)_4(1,4-bdoa)_2]

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Chinese Journal of Structural Chemistry 2005年第7期24卷 789-792,737页

作者： GAOShan LIUJi-Wei HUOLi-Hua ZHAOHui SchoolofChemistryandMaterialsscience HeilongjiangUniversityHarbin150080China SchoolofChemistryandMaterialsscience HeilongjiangUniversityHarbin150080China／／CollegeofChemistryandChemicalTechnologyDaqingPetroleumlnstituDaqing163318China

A novel dinuclear complex with an empirical formula [Co2(1H-benzimidazole)4(1, 4-bdoa)2] (1,4-bdoa2– = benzene-1,4-dioxyacetate dianion) has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. It crystallizes in monoclinic system, space group P21/c with a = 11.000(2), b = 19.385(4), c = 11.417(2) ?, β = 95.49(3)o, V = 2423.3(8) ?3, Z = 2, Mr = 1074.77, Dc = 1.473 g/cm3, μ = 0.760 mm–1, F(000) = 1108, the final R = 0.0645 and wR = 0.0714 for 3273 observed reflections (I > 2σ(I)). Two octahedrally coordinated Co(II) atoms are bridged by two 1,4-bdoa2– groups, generating a macrocyclic ring complex. The Co…Co separa- tion is 7.677(3) ?. An extended 3-D supramolecular network is formed through hydrogen bonds and weak π-π stacking interactions.

关键词： cobalt(II) complex benzene-1,4-dioxyacetic acid crystal structure

Formation and thermal stability of amorphous Ni-Mo-P alloys

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中国有色金属学会会刊：英文版 2004年第z1期14卷 147-151页

作者： ZHANG Yi MA Jun FANG Yong-kui DUAN Ji-guo School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China College of Chemistry and Chemical Engineering Daqing Petroleum Institute Daqing 163318 China College of Chemistry and Chemical Engineering Daqing Petroleum Institute Daqing 163318 China School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China

The experimental researches on the chemical deposition of Ni-Mo-P amorphous alloys were carried out by adding Na2 MoO4 into acidic solutions. The optimum technology conditions were obtained by orthogonal design experiments. The structures and the relationship between compositions and their thermal stability were studied by energy spectrum (EC), scanning electron micrograph and X-ray diffraction spectrum. Compared with Ni-P amorphous alloys, the Ni-Mo-P amorphous alloys have high crystallization temperature and thermal stability, and the hardness reaches its peak when the annealing temperature is 500 ℃. With the increase of the heat treatment temperature, the surface morphology of the alloys changes.

关键词： chemical deposition Ni-Mo-P alloy amorphous phase crystallization

Effect of extrusion ratio on the microstructure and texture evolution of AZ31 magnesium alloy by the staggered extrusion(SE)

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Journal of Magnesium and Alloys 2020年第4期8卷 1304-1313页

作者： Yan-peng Wang Feng Li Ye Wang Xue-wen Li Wen-win Fang School of Materials science and Engineering Harbin University of Science and TechnologyNo.4Lin Yuan StreetXiang FangHarbinHeilongjiang 150040China Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China

There are many problems with the conventional processes of magnesium alloy bending products,such as long processes and difficulty in controlling the product *** paper provides a staggered extrusion(SE)process to solve the above manufacturing *** effects of different extrusion ratios(λ)on the AZ31 magnesium alloy bending products prepared by the SE process was investigated in this *** results show that the bending radii of the AZ31 Mg bending products increase with the increase ofλat the same staggered distance(h=16 mm).When A is in creased from 11.11 to 44.44,the average bending radius of bending products is decreased from 14.7 mm to 9 mm,and the average grain size is decreased by 59.43%.After the SE process,the extruded fiber texture of the AZ31 Mg bending products is obvious,and the deformed texture is a mixed texture of{0001}(10-10)deformation texture and{10-11}(11-20)recrystallization *** results of XRD and EBSD showed that pyramidal slip is an important mode of crystal slip systems in AZ31 magnesium alloys during the SE *** provided a scientific basis for forming AZ31 Mg alloy bending products with excellent microstructure by the SE process.

关键词： Magnesium alloy Staggered extrusion(SE) Bending behavior Texture Slip

Wear Resistance of TiN_x/CF_y Coatings Deposited by RF Magnetron Co-Sputtering

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Journal of Materials science & Technology 2015年第12期31卷 1207-1216页

作者： Lin Zhu Jinwu Wang Zhuang Liu College of Engineering Northeast Agricultural University School of Light Industry Harbin University of Commerce

TiN x/CF y composite coatings were prepared by RF magnetron co-sputtering using twin cylindrical tube targets with Ar and N 2 *** composition of the coatings deposited at various positions was analyzed by X-ray photoelectron spectroscopy（XPS） and Rutherford back-scattering spectrometry（RBS）.The results revealed that the composition of the deposited coatings has a wide range of TiN x and CFy contents at different deposition positions,which leads to different structures and *** hardness of the composite coatings increases from 32 to 1603 HV with increasing the TiN x *** static contact angle of water ranges from 20° to 102° and decreases upon the incorporation of more TiN x into the CF y *** presence of the CF y groups enhances the contact angle between the coating and the solutions dropped onto it,which could effectively protect the coating from corrosion and improve the wear resistance properties in high relative humidity（RH）.The brittleness of the coatings decreases due to the softness of the CF y component,which can bear most of the load and result in less probability of crack *** results demonstrate the existence of a Ti-（C N） chemical bond in the composite coatings,which improves the wear resistance of the *** is indicated that the wear resistance of the TiN x/CF y coatings is independent of the ***,these properties depend on the uniform structure and the existence of chemical bonding between the TiN x and CF y ***,a specific ratio between the soft CF y phase and the hard TiN x phase can produce coatings with good wear resistance.

关键词： TiNx/CFy composite coatings Magnetron co-sputtering Wear resistance

Influence of microbial community structure of seed sludge on the properties of aerobic nitrifying granules

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Journal of Environmental sciences 2015年第9期27卷 144-150页

作者： Zhiwei Song Ting Li Qiuxu Wang Yu Pan Lixin Li School of Environment and Chemical Engineering Heilongjiang University of Science and Technology

In order to evaluate the influence of microbial community structure of seed sludge on the properties of aerobic nitrifying granules, these granules were cultivated with different seed sludge, and the variation of microbial community and dominant bacterial groups that impact the nitrogen removal efficiency of the aerobic nitrifying granules were analyzed and identified using 16 s rDNA sequence and denaturing gradient gel electrophoresis（DGGE） profiles. The results presented here demonstrated that the influence of the community structure of seed sludge on the properties of aerobic nitrifying granules was remarkable, and the granules cultivated by activated sludge from a beer wastewater treatment plant showed better performance, with a stable sludge volume index（SVI） value of 20 m L/g, high extracellular polymeric substance（EPS） content of 183.3 mg/L, high NH4＋-N removal rate of 89.42% and abundant microbial population with 10 dominant bacterial groups. This indicated that activated sludge with abundant communities is suitable for use as seed sludge in culturing aerobic nitrifying granules.

关键词： Microbial community structure Aerobic nitrifying granules Extracellular polymeric substance (EPS) 16s rDNA

Theoretical Study on Inverse Sandwich Complexes [E-C5-nH5-nNn-E]+ and [E-C5-nH5-nPn-E]+ (n=1, 2, 3;E=Al, Ga, In, Tl)

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： Nan-nan Liu Yi-hong Ding Chemistry Center College of Food Engineering Harbin University of Commerce Haerbin 150028China State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryJilin University Changchun 130012 China

The inverse sandwiches [E-C5?nH5?nNn-E]+ and [E-C5?nH5?nPn-E]+ (n=1, 2, 3; E=Al, Ga, In, Tl) with low-valent boron group elements are studied. The (η5, η5) coordinated inverse sandwich [E-C5?nH5?nNn-E]+ is unstable in energy or nonexistent. However, the (η5, η5) coordinated [E-C5?nH5?nPn-E]+ is not only stable in energy, but also stable against dissociation. The dissoction stability [E-C5?nH5?nPn-E]+ with the same E element decreases as the number n increases, while for the certain n number, the dissociation energies with different E elements are close to each other. [E-C4H4P-E]+ has similar dissocition stability to the well-known [E-C5H5-E]+. The inteaction between C5?nH5?nPn and low-valent E element is mainly ionic. Since lone pairs of electrons locate on both E and P atoms, the (η5, η5) coordinated inverse sandwich [E-C5?nH5?nPn-E]+ would act as multi electron-donors.

关键词： Low-valent Boron group elements Electron-donor Organometallic Heterocyclic

Impaired PI3K/Akt signal pathway and hepatocellular injury in high-fat fed rats

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World Journal of Gastroenterology 2010年第48期16卷 6111-6118页

作者： Ji-Wu Han,Department of Gastroenterology,The 4th Hospital of Harbin Medical University,Harbin 150001,heilongjiang province,China Xiao-Rong Zhan,Xin-Yu Li,Bing Xia,Yue-Ying Wang,Jing Zhang,Department of Endocrinology,First Hospital of Harbin Medical University,Harbin 150001,heilongjiang province,China Bao-Xin Li,Department of Pharmacology,State Key Laboratory of Biomedicine and Pharmacology,Harbin Medical University,Harbin 150001,heilongjiang province,China Department of Endocrinology First Hospital of Harbin Medical University Harbin 150001 Heilongjiang Province China. xiaorongzhan@***

AIM:To determine whether mitochondrial dysfunction resulting from high-fat diet is related to impairment of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt,also known as PKB) pathway. METHODS:Rat models of nonalcoholic fatty liver were established by high-fat diet feeding. The expression of total and phosphorylated P13K and Akt proteins in hepatocytes was determined by Western blotting. Degree of fat accumulation in liver was measured by hepatic triglyceride. Mitochondrial number and size were determined using quantitative morphometric analysis under transmission electron microscope. The permeability of the outer mitochondrial membrane was assessed by determining the potential gradient across this ***:After Wistar rats were fed with high-fat diet for 16 wk,their hepatocytes displayed an accumulation of fat (103.1 ± 12.6 vs 421.5 ± 19.7,P < 0.01),deformed mitochondria (9.0% ± 4.3% vs 83.0% ± 10.9%,P < 0.05),and a reduction in the mitochondrial membrane potential (389.385% ± 18.612% vs 249.121% ± 13.526%,P < 0.05). In addition,the expression of the phosphorylated P13K and Akt proteins in hepatocytes was reduced,as was the expression of the anti-apoptotic protein Bcl-2,while expression of the pro-apoptotic protein caspase-3 was increased. When animals were treated with pharmacological inhibitors of P13K or Akt,instead of high-fat diet,a similar pattern of hepatocellular fat accumulation,mitochondrial impairment,and change in the levels of PI3K,Akt,Bcl-2 was observed. CONCLUSION:High-fat diet appears to inhibit the PI3K/Akt signaling pathway,which may lead to hepa-tocellular injury through activation of the mitochondrial membrane pathway of apoptosis.

关键词： Nonalcoholic fatty liver Phosphatidylinositol 3-kinase/protein kinase B signaling pathway Mitochondria B-cell lymphoma gene 2 Caspase-3