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PRELIMINARY STUDY ON MAKINg OF wATER RESISTANCE wOOD FIBERBOARD

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Journal of Northeast Forestry University 1991年第2期2卷 54-60页

作者： Banks w.B. Jones g.L. North wales University North Wales University United KingdomUnited Kingdom

In the present study,described that preparation of oligoesterified wood fibre by theaddition reaction of the wood fibre with maleic anhydride(MA)and allyl glycidyl ether(AgE).Further,made of crosslinkable oligoesterified fiber board at high temperature and underhigh pressues,accompanying plasticization of the wood fibre *** product exhibitedthe high the modulus of repture in bending(MOR),good water repellency and dimesionalstability.

关键词： wood fibre Oligoestcriflcation Fiberboard

INFLUENCES OF DENSITY AND DIMENSION OF CARBON NANOTUBES ON THEIR FIELD EMISSION

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Acta Metallurgica Sinica(English Letters) 2003年第4期16卷 302-308页

作者： Y.B.Zhu w.L.wang C.g.Hu DepartmentofPhysics JiangsuNormalUniversitySuzhou221009ChinaManuscriptreceived25November2002 DepartmentofAppliedPhysics ChongqingUniversityChongqing400044China

The influences of density and dimension of carbon nanotubes on their electron emission from arrays are studied. The tip electric field of nanotubes, electric field enhancement factor, and optimum nanotube density are expressed by analytic equations. The theoretical analyses show that the field enhancement factor is sensitive to nanotube density, and can be sharply improved at a specific and optimum density. Some experiments have demonstrated these. Owning to electrostatic screening effect, the length of carbon nanotubes has little effect on their emission. A uniformly-distributed carbon nanotube array model is set up, and applied to analysis of carbon nanotube arrays. The results obtained here are in good agreement with the experimental data.

关键词： carbon nanotube array field emission optimum density

Identifying fish assemblages in tropical lagoon ecosystem:First record from Luang Island,South-west Maluku Indonesia

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Aquaculture and Fisheries 2023年第2期8卷 221-226页

作者： B.g.Hutubessy Jacobus w.Mosse Department of Fisheries Resource Utilization Pattimura UniversityJl.Mr.Chr.SoplanitKampus PokaAmbon97233Indonesia Department of Aquaculture Pattimura UniversityJl.Mr.Chr.SoplanitKampus PokaAmbon97233Indonesia

The aim of this study was to record demersal species from lagoon in Luang Island,a small and remote island in Maluku,*** and qualitative methods were employed with the assistance of the local fishers using 4 different methods of fishing:gillnets,spear guns,traps,and *** knowledge informed fish abundance and frequency of occurrence.A total of 348 individual fish distributed across 53 species were recorded from the catch of 4 gear ***-Curtis similarity scores of fish assemblages at different habitats was ranged from 7.19%to 10.35%.The nMDS bi-plot visualized a distinct dimension with which to allocate 3 habitats separately from the sand-seagrass *** similarity of species at 4 different habitats(ANOSIM R^(2)=0.124,P=0.002)suggested that the habitat parameter was not able to predict different communities of *** paper is the first contribution on the composition of lagoon ichthyofaunal in Southwest Maluku *** attitude towards marine resource exploitation such as traditional conservation,less fishing pressure and marine culture will maintain the healthy ichthyofaunal assemblages in a tropical lagoon ecosystem.

关键词： Species composition Remote Island Unstudied area Fishers’knowledge

Co-deposition of Co-Ni alloys and their microstructure analysis by PoSAP

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Chinese Science Bulletin 1997年第23期42卷 2013-2014页

作者： R.A.D.Mackenzie g.D.w.Smith Department of Materials University of Oxford Parks Road Oxford OX1 3PH UKDepartment of Materials University of Oxford Parks Road Oxford OX1 3PH UK

PULSED-co-electrodeposition （PCD） is a new and promising technique for producing alloymaterials of nanometer grain size. In this letter, Co-Ni alloys were produced by PCD, and theeffect of CO+2 ion concentration in the depositing baths on the Co content and the microstruc-ture in the corresponding deposit was studied by the position sensitive atom probe （PoSAP）,TEM and X-ray diffraction. The Co-Ni phase diagram shows that, at room temperature,there are two phases in Co-Ni alloys, one is εCo with hcp lattice, the other is αCo of fcc lat-tice. A Co-Ni alloy with a Ni content below 27% consists of single εCo, beyond 36% consistsof single αCo, in between consists of εCo + αCo. The examination results of TEM, SEM andX-ray diffraction indicated that the Co-Ni deposits with average grain size of 70 nm and thick-

关键词： Co-deposition of Co-Ni alloys and their microstructure analysis by PoSAP Ni

An experimental investigation into modeling solids friction for fluidized dense-phase pneumatic transport of powders

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Particuology 2017年第1期15卷 83-91页

作者： g. Setia S.S. Mallick R. Pan P.w. wypych Department of Mechanical Engineering Thapar University Patiala Punjab 147004 India Fujian Longking Co. Ltd. 81 Lingyuan Road Longyan City Fujian 361000 China Faculty of Engineering University ofWollongong WoUongong NSW2522 Australia

Results are presented of an ongoing investigation into modeling friction in fiuidized dense-phase pneumatic transport of bulk solids. Many popular modeling methods of the solids friction use the dimen- sionless solids loading ratio and Froude number. when evaluated under proper scale-up conditions of pipe diameter and length, many of these models have resulted in significant inaccuracy. A technique for modeling solids friction has been developed using a new combination of dimensionless numbers, volu- metric loading ratio and the ratio of particle free settling velocity to superficial conveying air velocity, to replace the solids loading ratio and Froude number. The models developed using the new formalism were evaluated for accuracy and stability under significant scale-up conditions for four different prod- ucts conveyed through four different test rigs （subject to diameter and length scale-up conditions）. The new model considerably improves predictions compared with those obtained using the existing model, especially in the dense-phase region. whereas the latter yields absolute average relative errors varying between 10% and 86%, the former yielded results with errors from 4% to 20% for a wide range of scale-up conditions. This represents a more reliable and narrower range of prediction that is suitable for industrial scale-up requirements.

关键词： Fluidized dense-phase Pneumatic transport Solids friction factor Scale-up Volumetric loading ratio Dimensionless velocity

Characteristic Polynomial Assignment in 2-D System

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Journal of Systems Engineering and Electronics 2001年第3期12卷 57-63页

作者： Liu, Z. Zhao, S. Tang, w. Li, g. Tianjin University Tianjin 300072 China

The closed loop polynomial assignment problems of 2D systems Roesser model with multiple inputs were studied. The problems were transferred to a rational map and were assigned a sate feedback and output feedback. Suff... 详细信息

关键词： Computational complexity Computational geometry Image processing Kalman filtering Mathematical models Matrix algebra Polynomials State feedback

Reproductive biology of the greater bandicoot rat Bandicota indica(Rodentia:Muridae) in the rice fields of southern Thailand

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Current Zoology 2009年第1期55卷 48-55页

作者： N.THITIPRAMOTE J.SUwANJARAT w.g.BREED Department of Biology Faculty of SciencePrince of Songkla University Discipline of Anatomical Sciences School of Medical SciencesFaculty of Health SciencesThe University of Adelaide

This study investigated some aspects of the reproductive biology of male and female greater bandicoot rats, Bandicota indica, in southern Thailand from September 2004 to September 2006. In females, body, uterine and preputial gland weights, occurrences of pregnancies and placental scars, and in males, testicular weights and histology, and sizes of accessory sex glands, were recorded. Pregnancies occurred predominantly, but not exclusively, in the wet season, with a higher incidence pregnancies in the second, than in the first, dry season. Uterine and preputial gland weights tended to be lower in the first, but not the second dry season, with placental scars occurring at all times of year. Males tended to have heavier testes in the wet season but some seminiferous tubules contained sperm even in the dry season. Seminal vesicles, but not prostates and preputial glands, tended to be heavier in animals in the wet season. we conclude that the greater bandicoot rat in southern Thailand shows maximal reproductive activity in the wet season with some reproductive activity, albeit variable from year to year, occurring in the dry season depending upon environmental conditions. This study has also shown that females, as well as males, have large preputial glands, and that males invariably have small testes regardless of the time of year. These observations suggest a similar timing of reproduction, but a different breeding biology and perhaps social organisation, from that of the sylnpatric ricefield rat, Rattus argentiventer.

关键词： greater bandicoot rat Bandicota indica Time of breeding Testis size

AN INVESTIgATION OF HIgH-TEMPERATURE DEFORMATION STRENgTHENINg AND TOUgHENINg MECHANISM OF TITANIUM ALLOY

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Acta Metallurgica Sinica(English Letters) 1998年第5期11卷 376-382页

作者： Y.g.Zhou w.D.Zing H.Q.Yu Northwestern Polytechnical Univ Xi'an China

The high-temperature deformation strengthening and toughening mechanisms of titanium alloys have been investigated in this paper. The materials processed by this method produce a new tri-modal microstrvcture, which consists of 10-20% equiaxed alpha, streaky alpha and transformed beta matrix. It is found that the higher ductility of tri-modal microstructure is attributed to the equiaxed alpha's coopemtive slip and coordinated deformation with the transformed beta matrix. The streaky alpha phases not only increase the strength and creep properties, but also increase the fracture toughness. Propagating along grain boundaries between two neighboring streaky alpha phases, cracks in tri-modal microstructure make a more tortuous way, and then the materials show a higher fracture toughness. This new method is applicable to α, near α,α+β and near β titanium alloys.

关键词： titanium alloy high-temperature deformation strengthening and toughening mechanism

TENSILE STRESS RELAXATION OF TURBINE BOLT STEELS AT HIgH TEMPERATURE

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 542-547页

作者： g.Q.Jia H.w.Shen Y.M.Zhu Metallurgical Department. Shanghai Turbine Company Ltd. Shanghai 200240 ChinaMetallurgical Department. Shanghai Turbine Company Ltd. Shanghai 200240 ChinaMetallurgical Department. Shanghai Turbine Company Ltd. Shanghai 200240 China

Stress relaxation behavior of two turbine bolt steels was evaluated by the manual-controlled tensile stress relaxation test (TSRT) at high temperature. First, feasibility and the procedure of the manual-controlled tensile stress relaxation test (TSRT) is discussed and carried out on a general creep testing machine. And then, the experimental results from such type of test were compared to the existing data provided by certain Laboratory U.K. Overall good agreement between the results of manual-controlled TSRT method and the existing data provides confidence in the use of the proposed method in practice. Finally, the experimental results of turbine bolt steels from TSRT were compared with that of bending test. It is observed that great difference exists between the results from two different type stress relaxation tests. It is therefore suggested that the results from TSRT method be adopted in turbine bolt design in engineering.

关键词： tensile stress-relaxation test bending stress-relaxation test turbine bolt steels