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Cooperative Exploration for Rare Metals Mine with JapanAt Zhanjing,Guangdong Province,three large-scale rare metals deposits have been found.Five kinds of ores including the titanic iron ores、zircon etc totalled 5.79 millions tonnes.Amongthem 3.10 Mt have been explored tentatively in respect of exploitative environment.The UnugturMountain copper-molybdenum mine,Inner Mongolia Autonomous Region,has been explored indetail;it is suggested that the reserves of copper are 560 kt,the molybdenum reserves are 200 kt.The Project of comprehensive Exploration of Rare Metals is carried out cooperatively by Chinaand Japan over six years.     

Microstructure and properties of modified and conventional 718 alloys

Continuing the effort to redesign IN718 alloy in order to provide microstructural and mechanical stability beyond 650 ℃, IN718 alloy was modified by increasing the Al, P and 13 contents, and the microstructure and mechanical properties of the modified alloy were compared with those of the conventional alloy by SEM and TEM. The precipitation of the grain boundaries of the two alloys is different. The Cr-rich phase, Laves phase and α-Cr phase are easily observed in the modified alloy. The γ＂ and γ＇ phases in the modified alloy are precipitated in a ＂compact form＂. The tensile strengths of the modified alloy at room temperature and 680 ℃ are obviously higher than those of the conventional one. The impact energy of the modified alloy is only about half of that of the conventional alloy. Ageing at 680 ℃ up to 1000 h lowers the tensile properties and impact energy of both the conventional and modified 718 alloys, except increasing the ductility at 680 ℃. It is concluded that the modified alloy is more stable than the conventional one.     

Dissolution Behaviour and Electrodeposition of Strontium and its Alloys

The electromotive force(EMF)was determined by electrochemical method at 760～950℃ for the concen-tration cell:(Mo)Sr|SrCl_2,--Sr sat.||SrCl_2,--xSr|Mo. The dissolution behavior of Sr and alloyed strontium(i.e.Cu--Sr or Al--Sr) in molten salt containing SrCl_2 was studied. The electrolysis of SrCl_2 for production ofSr and its alloys(Al-Sr and Cu-Sr) was also conducted on the basis of electrochemical measurement. The disso-lution data so obtained well agree with the results from phase diagram.     

Microstructures and mechanical properties of Al-Mg and Al-Zn-Mg based alloys containing minor scandium and zirconium

1　INTRODUCTIONAddingofminorMn ,Cr ,Ti,B ,Zr ,Sc ,Agintoaluminumalloyscanremarkablychangethemi crostructuresandpropertiesofaluminumalloys[18] .Amongthem ,theeffectofminorScandZrhasre ceivedspecialattention .Onthe 1stInternationalScandiumConferenceheldinMoscowin 1994 ,Rus sianmetallurgistsdescribedtheapplicationprospectofaluminumalloyscontainingScinaerospace ,aviation ,warshipsandnuclearindustry ,whichhasstimulatedmanyindustrialcountries’researchinterestinthiskindofalloys .Atpresent…     

Microstructure and properties of β-NiAl and its eutectic alloy with Cr and Mo additions

NiAl-0.3Ru and NiAl-30Cr-4Mo alloys were fabricated by arc melting method and then annealed at 1 423 K for 12 h. It has been revealed that NiAl-0.3Ru was in a single-phase with large grain size and NiAl-30Cr-4Mo consisted of multiple eutectic cells. Each cell consisted of alternating plates NiAl and Cr（Mo）. The compressive properties including the brittle-ductile transition temperature （BDTT） were tested. NiAl-0.3Ru and NiAl-30Cr-4Mo fractured with a little plastic deformation after yielding below the BDTT, and almost no fracture was found after large deformation up to 60% above the BDTT. Fractograph showed that at the room temperature, the fracture in NiAl-0.3Ru was intergranular and the NiAl-30Cr-4Mo in transgranular along the interface between fiNiAl and Cr （Mo）. The compressive properties of NiAl were obviously improved by eutectic alloying with Mo and Cr additions.     

Wear and corrosion resistance of laser remelted and plasma sprayed Ni and Cr coatings on copper

Nickel and chromium coatings were produced on the copper sheet using plasma spraying and laser remelting. The sliding wear test was achieved on a block-on-ring tester and the corrosion test was carried out in an acidic atmosphere. The corrosive behaviors of both coatings and original copper samples were investigated by using an impedance comparison method. The experimental results show that the nickel and chromium coatings display better wear resistance and corrosion resistance relative to the original pure copper sample. The wear resistance of the coatings is 8 - 12 times as large as original samples, and the wear resistance of laser remelted samples is better than that of plasma sprayed ones. The corrosion resistance of laser remelted nickel and chromium samples is better than that of plasma sprayed samples respectively. The corrosion rate of chromium coatings is less than that of nickel coatings, and the laser remelted Cr coating exhibits the least corrosion rate.     

Solid atomization technology and process of molten metal and alloy

A novel solid atomization technology,which using high velocity gas jet-stream rich in solid salt particles as atomization medium,was developed.The results show that using this novel atomization process can produce various metal and alloy powders with finer paricle size,finer microstructures and higher cooling rate than those powders produced by the conventional gas atomization technology.     

Synthesis and purification of trialkyl compounds of gallium and indium

The research progress in trialkyl compounds of gallium and indium was discussed from two aspects, one was the chemical synthesis of the compounds and the other was the purification of them. There are three synthesis routes being reported in the first aspect, i.e. the route staring from pure metal, the route starting from the pure metal trihalides, and the electrochemical route. In the second aspect, the purifying methods of decomposition-distillation and zone refining were reviewed.     

Intensifying digestion of diaspore and separation of alumina and silica

1　INTRODUCTIONDespitetheabundantdepositofbauxitesinChi na ,ofthosepredominantisthediasporictypewithhighalumina ,highsilicaandlowferricoxides .Thebauxitedeposit,withthemassratioofaluminatosil ica(A/S)between 4and 8,accountsfor 80 %ofallthebauxitedeposit.Thenatureofhighsilicacontentdeterminesthatthemainlyadoptedtechniquetopro ducealuminainChinashouldbeBayer sinteringcom binationprocessorevenpuresinteringprocess .Althoughadramaticadvancementinaluminaproductionhasbeenachievedandthetechnolo…     

Growth and Application of Chalcogenides of Lead and Related Compounds

Large grain, low-dislocation, high-quality single crystals of various Pb-salt compounds have been grownreproducibly by the Horizontal Unseeded Vapor Growth (HUVG) technique. The Tunable Diode Lasers withbetter performance have been made with such crystals. The annealing feature, dislocations and diffusion in thecrystals have also been investigated.     

4.5与7.5月龄雌性Sprague-Dawley 大鼠骨代谢的变化

目的:观察雌性SD 大鼠4.5月龄和7.5月龄时骨代谢的变化。方法:4 月龄雌性SD 大鼠20 只, 随机分2 组, 饲养至4.5月龄和7.5月龄时, 用骨组织形态计量学分别测量胫骨上段(PTM)、腰椎(LV) 及胫骨中段(Tx) 的静态参数和动态参数。结果:与4.5月龄比较, 7.5月龄大鼠PTM、LV、Tx 的骨量无明显变化, 但LV 和Tx 的骨形成参数标记周长百分数(%L.Pm)、矿化沉积率(MAR) 及骨形成率BFR/TV、BFR/BV、BFR/BS 均降低。结论:SD 大鼠在4.5～7.5月龄时, 松质骨和皮质骨的骨量变化不明显, 但腰椎和胫骨中段的骨形成随月龄增加而降低。     

不同月龄正常大鼠骨形态计量学参数动态变化的研究

目的:探讨不同月龄正常大鼠骨形态计量学参数变化, 为抗骨质疏松药物研究提供对照依据。方法:4.5 月龄SD 雌性大鼠, 按体重随机分组, 在实验的d 0(4.5 月龄)、d 30 (5.5 月龄)、d 75 (7 月龄)、d 140 (10 月龄) 杀死大鼠取材, 采用体内双荧光标记法, 胫骨上段硬组织包埋切片及松质骨形态计量学分析, 观察不同月龄段大鼠的骨变化情况。结果:正常大鼠4.5～10 月龄, 骨量有一缓慢上升后下降的过程, 但变化辐度不大(P>0.05), 骨量相对稳定, 骨形成和骨吸收有先上升后下降的变化过程(P<0.05) 。结论:4.5～10 月龄的SD 雌性大鼠体重和骨计量学参数变化正常, 选择该月龄段大鼠做模型, 研究药物对骨质疏松的防治是可行的。     

大鼠去卵巢后对不同部位骨骼的影响

目的: 观察大鼠去卵巢90 d 后不同部位骨骼的变化特点。方法: 4. 5 月龄雌性SD 大鼠20 只, 随机分为假手术组和去卵巢组, 均灌喂5. 6 %乙醇5 ml·kg^-1·d^-1, 持续90 d, 用骨组织形态计量学方法测量胫骨上段和腰椎松质骨及胫骨中段皮质骨的动态和静态参数。结果: 去卵巢大鼠胫骨上段(PTM) 和腰椎(LV) 松质骨的骨量均减少, 其中PTM骨量减少80. 5 %, LV 骨量减少35. 0 %, 胫骨中段(Tx) 皮质骨的骨量未出现丢失, 只是骨内、外膜的骨形成增加。结论: 大鼠去卵巢后呈现高转换型骨质疏松表现, 不同部位的骨骼变化不同。     

纯钛表面PPy／rhBMP-2复合涂层对骨髓间充质干细胞增殖、分化的影响

采用水溶液恒电流电化学聚合法在纯钛表面制备了聚吡咯／重组人骨形成蛋白涂层（Ti／PPy／rhBMP-2）。利用循环伏安扫描分析涂层氧化还原性质，^125I蛋白质标记法检测rhBMP-2掺杂量，表面粗糙度仪、扫描电子显微镜检测涂层微观形貌。通过对骨髓间充质干细胞（BMSCs）在Ti／PPy／rhBMP-2表面增殖、分化能力的检测，评价Ti／PPy／rhBMP-2对骨髓间充质干细胞增殖、分化的影响。结果表明，rhBMP-2能够以聚电解质阴离子方式稳定地掺杂于PPy结构中，并且所生成的涂层表面粗糙度高且结构疏松。Ti／PPy／rhBMP-2中掺杂固定的rhBMP-2依然保持着其骨诱导活性，能够促进BMSCs的增殖、分化。     

淫羊藿总黄酮对去卵巢大鼠骨骼的影响

目的: 观察淫羊藿总黄酮(EF) 对去卵巢大鼠骨骼的影响。方法: 4.5 月龄雌性SD 大鼠40 只, 随机分为假手术组、去卵巢组、己烯雌酚(DES) 组和淫羊藿总黄酮组。己烯雌酚组和淫羊藿总黄酮组大鼠行双侧卵巢去除术后, 分别灌喂DES 22.5μg·kg^-1·d^-1、EF 300 mg·kg^-1·d^-1, 持续90 d。用骨组织形态计量学等方法测量胫骨上段和第5 腰椎松质骨及胫骨中段皮质骨的动态参数和静态参数, 同时测量股骨钙、磷及羟脯氨酸含量, 测量子宫湿重及子宫内膜厚度。结果: 淫羊藿总黄酮可使去卵巢大鼠股骨钙、磷含量增加, 胫骨上段的骨量有增加的趋势, 但无统计学意义, 腰椎和胫骨中段皮质骨的变化均不明显, 子宫湿重及子宫内膜厚度也无明显变化。结论: 淫羊藿总黄酮能有效预防去卵巢大鼠的股骨丢失, 但不能有效预防胫骨上段和腰椎松质骨的丢失, 对子宫没有刺激作用。     

珍珠层，一种具有潜力的天然骨修复材料

由于骨质疏松、骨折、骨肿瘤等原因导致的骨缺损困扰着世界上成千上万的人。近年来，关于骨缺损修复材料的研究已得到了国内外科研工作者的广泛关注。珍珠层是组成许多软体动物贝壳的结构单元之一。与骨组织类似，珍珠层也是一种由无机相矿物与有机基质组成的复合材料。虽然珍珠层与骨组织具有非同源性，但是，其部分的形成机理可能具有类似性。介绍了近年来国内外关于珍珠层研究的大量体外与体内试验，试验结果表明了珍珠层具有良好的生物相容性与成骨特性，有可能成为一种具有潜力的天然骨修复材料。珍珠层的成骨特性很有可能来源于其有机基质中的未知信号因子。同时也指出了珍珠层用作天然骨修复材料在今后研究中的机遇与挑战。     

Doping of Strontium into Natural Bone Powder and Further Cell Experiment

优良的骨修复材料可以缩短骨愈合周期,降低不愈合的发生率。锶离子被发现具有促进骨形成的作用,将锶元素掺入骨粉材料将可能制作出一种有前景的骨修复材料。在研究中锶元素被尝试通过离子交换的方法掺入骨粉材料,实验观察了锶元素掺入骨质中的能力。新材料的细胞毒性通过MTT方法进行评价。原代培养的成骨细胞被用来评价新材料的生物相容性。结果发现锶元素在骨粉中的掺入比例可以高达10%,新材料没有细胞毒性,与普通骨粉相比成骨细胞的相对增殖率达到后者的129%,ALP活性则达到后者的132%。因此,通过离子交换方法可以制备性能优异的掺锶同种骨粉移植材料。     

组织工程化三维仿骨支架重建股骨头坏死区研究

首先研制出具有取向性类骨结构的β-TCP三维仿骨支架,经过仿生类骨处理和组织工程化后,植入犬的股骨头坏死区,30周后取出股骨头进行分析研究.与此同时开展了几种支架材料重建股骨头坏死区的力学性能分析和模拟.结果显示,具有取向性类骨结构的β-TCP三维仿骨支架具有很好的生物相容性和力学相容性.动物实验研究表明:组织工程化三维仿骨支架诱导生长出新的骨小梁,并伴有β-TCP降解,这为修复或重建股骨头局部坏死区提供了一种有希望的新途径.     

快速成型模板调制双相掺锶磷酸钙陶瓷骨支架的结构与性能

以高强可降解掺锶磷灰石骨水泥(Sr-HAC)为原料,以快速成型(RP)宏孔可控树脂为模板,合成了由掺锶磷灰石(Sr-HA)、掺锶磷酸钙(Sr-TCP)组成的新型双相掺锶磷酸钙(Sr-BCP)骨支架。结果表明,Sr-BCP骨支架相组成可根据Sr-HAC的(Ca+Sr)/P比率予以调控。骨支架宏孔高度连通,孔径400～550μm,且宏孔壁上具有丰富的微孔(孔径2～5μm)。此外,骨支架宏孔参数可通过设计不同孔结构的负模予以反向调控。宏孔百分数与相组成对Sr-BCP支架的抗压强度与降解速率有重要影响。与BCP骨支架相比,Sr-BCP骨支架具有更高的强度及更快的降解速率,一定程度上缓解了BCP陶瓷骨支架在力学和降解性能上难以兼顾的矛盾。