首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 187 毫秒
1.
The most effective fumigant for insect disinfestation of cut flowers is currently methyl bromide, which will soon be unavailable in several countries. The toxicity of an alternative fumigant, phosphine (2% PH3 and 98% N2), was tested at 24 °C on adult greenhouse thrips (Heliothrips haemorrhoidalis), adult aphids (Myzus persicae) and lightbrown apple moth larvae (LBAM; Epiphyas postvittana). These are commonly found as insect pests on many cut flower crops. Thrips were exposed to phosphine concentrations ranging from 20–600 μl/l for 1 or 2 h. All thrips were killed within 18 h of exposure after a treatment of 300 μl/l phosphine for 2 h. Adult aphids and fifth instar LBAM larvae were more resistant to phosphine, and trials were therefore conducted using higher phosphine concentrations (> 500 μl/l) combined with atmospheric (0.035%) or elevated (33%) CO2. The most effective treatment for aphids was 1000 μl/l phosphine + 33% CO2 for 4 h, which killed all insects within 36 h of exposure. Under atmospheric CO2, levels, 92% of aphids were killed within 36 h after exposure to 1000 μl/l phosphine for 6 h, with 100% kill attained after exposure to 5000–8000 μl/l phosphine for 6 h. Elevated CO2 levels did not improve the efficacy of phosphine on LBAM larvae. The optimal treatment was 2000–2500 μl/l phosphine for 4 or 6 h, which killed 96 or 100% of the larvae, respectively. Under atmospheric CO2 levels, 4000 μl/l phosphine killed 74% of LBAM larvae after 4 h, and 94% after 6 h exposure.  相似文献   

2.
Ten field pea genotypes were evaluated in randomized complete block design with four replications for three consecutive years (2010-2012) main cropping seasons at four locations in each year. The objectives were to determine magnitude of genotype by environment interaction and to identify stable field pea genotype with high grain yield to be released as a cultivar to producer for Northwestern Ethiopia. The GGE [genotype main effect (G) and genotype by environment interaction (GE)] biplot graphical tool was used to analyze yield data. The combined analysis of variance revealed a significant difference (P<0.01) among genotypes, environments and genotype-by-environment interaction for grain yield. The average environment coordinate biplot revealed that EH99005-7 (G2) was the most stable and the highest yielding genotype. Polygon view of GGE-biplot showed the presence of three mega-environments. The first section includes the test environments E1 (Adet 2010), E3 (Debretabor 2010), E5 (Adet 2011), E6 (Motta 2011), E7 (Debretabor 2011), E8 (Dabat 2011), E9 (Adet 2012) and E12 (Dabat 2012) which had the variety G1 (EH99009-1) as the winner; the second section contains the environments E4 (Dabat 2010), E10 (Motta 2012) and E11 (Debretabor 2012) with G2 as the best grain yielder and the third section contains the E2 (Motta 2010) with G4 (Tegegnech X EH90026-1-3-1) as the best grain yielder. The comparison GGE- biplot of field pea genotypes with the ideal genotype showed that G2 was the closest genotype for the ideal cultivar. Among the twelve environments, E2, E6 and E10 were more discriminating and E3, E9 and E12 were less discriminating. Genotype EH99005-7 was the most stable and the highest yielding genotype. As a result it is released officially for Northwestern Ethiopia. Therefore, it is recommended to use genotype EH99005-7 for wider cultivation in Northwestern Ethiopia and similar areas.  相似文献   

3.
Anthers of Brassica nigra, excised from fresh as well as cold-pretreated (3 days at 3 ± 2°C) buds cultivated on modified B5 medium (Gamborg et al. 1968) containing sucrose level varying from 2 % to 10 %, along with 1O?6M BAP (benzylaminopurine) and 9 × 10?6M 2,4-D (2,4-dichlorophenoxyacetic acid), developed calli and/or embryos. The latter response was observed only in anthers reared on media containing 6 % or higher levels of sucrose. On media containing two or four per cent sucrose, the anthers produced calli, exclusively. The growth of embryos was inhibited or else they started callusing if left on the media containing higher levels of sucrose. However, on transfer to MS medium (Murashige and Skoog 1962), containing 2 % sucrose, embryos started callusing and subsequently a few secondary embryos differentiated. Such embryos were sub-cultured on MS + 5 × 10?6M BAP + 2 % sucrose, wherein numerous shoots developed from embryos. The shoots were rooted by transferring to a medium containing 5 × 10?6M NAA (naphthalene acetic acid). Within two months of culture, some of these plants started flowering in vitro.  相似文献   

4.
宁夏枣树品种品系的AFLP分析   总被引:1,自引:1,他引:1  
摘 要: 应用基因组DNA-AFLP分子标记技术,对原产宁夏回族自治区的8个枣树品种品系和原产甘肃靖远县的1个枣树品种的亲缘关系进行了研究。研究结果表明,5对引物(E1/M12、E1/M4、E4/M11、E2/M10和E5/M4)扩增出了466条带,其中多态性条带为130条,多态性比率达27.89%,表明遗传多样性不是很丰富。聚类结果证明灵武长枣2号与中卫大枣、同心圆枣聚为一类,彼此间近缘关系较近,而与灵武长枣品种的亲缘关系较远,是一个新种质;同心圆枣与中卫大枣的遗传距离仅为0.015,亲缘关系最近,是同物异名。  相似文献   

5.
水稻雄性不育系新露A的抽穗期基因型分析   总被引:5,自引:0,他引:5  
水稻雄性不育系新露A是一个粳质籼核优质不育系, 其所配组合的抽穗期多数表现为超或偏早亲遗传. 本文利用抽穗期基因型明确的秋光(e1e1 e2e2 e3e3 Se-1eSe-1e)、越光(E1E1 E2E2 e3e3 Se-1eSe-1e)和日本晴(E1E1 e2e2 e3e3 Se-1nSe-1n)作测验品种, 分析了新露B的抽穗期基因型, 结果表明: 其抽穗期感光基因型为: e1e1 e2e2 e3e3  相似文献   

6.
为了明确甜玉米种质资源的遗传多样性,试验利用过氧化物酶高度保守区域设计引物对34份甜玉米种质进行过氧化物酶基因多态性分析。结果表明,10对引物扩增出了34条DNA条带,其中21条具有多态性,占总带数的61.76%;聚类分析表明,其相似系数变化范围在0.674~0.978之间,平均为0.826。基于欧氏距离,供试甜玉米材料被划分为4个类群(Fresh corn groups,简称FCGs)。FCGⅠ含有9份资源,其中姊妹系普通甜玉米紫Su 5-12、紫Su 5-3分在此类中;FCGⅡ和FCGⅢ分别包括6份和7份;FCGⅣ包括12份甜玉米种质,超甜玉米姊妹系M 638和M 616被划分在此类中。  相似文献   

7.
Male fertility restoration in new types of sorghum cytoplasmic male sterility‐inducing cytoplasms (A4, ‘9E’, ‘M35’), characterized by the formation of non‐dehiscent anthers, is difficult. Lines with fertility‐restorer genes for these unique cytoplasms do occur, but rarely, and when found tend to be unstable in their inheritance and expression. The aim of this research was to explore reasons for this instability. Seven lines in three unique cytoplasms, ‘9E’, A4 and ‘M35’, and six lines that restore with these cytoplasms were grown at the Agricultural Research Institute for South‐East Region in Saratov, Russia from 1993 to 2004. Levels of male fertility restoration and various environmental factors were recorded. It is reported that for sorghum hybrids in the A4, ‘9E’ and ‘M35’ male‐sterile cytoplasms, the level of plant male fertility is determined by the level of water available to plants during anther and pollen formation that which ‘switches on’ the expression of fertility‐restoring genes, and is possibly involved in an unusual type of male fertility inheritance in these cytoplasms. The creation of reliable line‐fertility restorers capable of the restoration of male fertility of F1 hybrids in ‘M35’ cytoplasm under conditions of water stress is also reported. Current research explore mechanisms involved possible in responses to water levels at various growth stages and their influence on fertility within these cytoplasms.  相似文献   

8.
在碱性条件下采用改良化学共沉淀法制备具有超顺磁性的Fe3O4纳米粒子,并用红外光谱仪、X射线衍射仪、透射电子显微镜和振动样品磁强计对所制得Fe3O4粒子进行表征。结果表明,该试验条件下制备的样品其红外光谱图和XRD谱图与标准Fe3O4粒子的物态和晶相结构基本一致;透射电镜表明制备出Fe3O4粒子成球性好,且大部分粒径在14 nm;磁化曲线也表明制备的Fe3O4粒子无剩磁和矫顽力,具有超顺磁性。  相似文献   

9.
烤烟香气物质成分及其在成熟期间的变化   总被引:11,自引:0,他引:11  
使用气相—质谱—计算机联用仪,完成了对烤烟品种NC_(89)香气物质主要成分的定性鉴定,并对主要成分的香型进行了嗅香评定。在此基础上,对不同成熟时期的烟叶香气物质主要成分进行了定量分析。  相似文献   

10.
According to Electrodynamics in curved spacetime, the interaction between gravitational waves (GW) and electromagnetic (EM) fields will produce perturbative electromagnetic fields. In a special EM system, namely, a Gaussian beam (Gb) propagating through a static magnetic field, the photon flux along the direction of the electric field of the Gb will be only a pure perturbative photon flux,when a GW propagates along the symmetric axis of a Gaussian beam. Detailed alanysis and calculation of the photon flux along several typical surfaces are performed, and a possible optimum plane which can receive perturbative photons up to 10~4s~(-1) is proposed. It is possible to provide an important method to detection of GW.  相似文献   

11.
Summary Analysis of individual parts of Triticum aestivum L. and T. turgidum var. durum kernels showed two classes of alcohol dehydrogenase patterns: 1) A three banded pattern (ADH-1, ADH-2 and ADH-3) for endosperm (Ed) and 2) a seven banded pattern (ADH-F1, ADH-F2, ADH-1, ADH-2, ADH-3, ADH-S1 and ADH-S2) for embryo (E), scutellum (S) and embryo plus scutellum (E+S). The use of nullitetrasomic and ditelosomic series of Chinese Spring wheat allows alcohol dehydrogenase to be associated with arms 4A, 4BL and 4DS.A five subunit forming dimer hypothesis is postulated to explain the newly reported seven isozyme pattern. Subunits , and are coded by chromosome arms 4A, 4BL and 4DS respectively, and the newly postulated and are coded also by chromosome arm 4BL.  相似文献   

12.
R. Bošković  K.R. Tobutt 《Euphytica》1998,103(3):273-286
Two interspecific cherry progenies, Prunus avium ‘Napoleon’ × P. incisa E621 and ‘Napoleon’ × P. nipponica F1292, were analysed with polyacrylamide gel electrophoresis for 19 enzyme systems: alanine aminopeptidase (AAP), aldolase (ALD), alkaline phosphatase (AKP), arginine aminopeptidase (ARA), catechol oxidase (CO), diaphorase (DIA), endopeptidase (ENP), esterase (EST), formate dehydrogenase (FDH), fructose-bisphosphatase (FBP), β-galactosidase (GAL), glucose-6-phosphate dehydrogenase (G6PDH), β-glucosidase (GLU), glutamate dehydrogenase (GDH), glyceraldehyde-3-phosphate dehydrogenase (G3PDH), hexokinase (HEX), peroxidase (PRX), phosphorylase (PHO) and triose-phosphate isomerase (TPI). Activity for GAL was identical with GLU, and CO with PRX. In addition, activity for AKP was identical with some regions detected previously as acid phosphatase; and most of the PRX activity was identical with regions detected previously as superoxide dismutase. In all, 16 new segregating loci were identified, Ara-1, Dia-2, Est-1, Est-2, -6, -7 and -9, Glu-1 to -4, Hex-1, Pho-1 and -2, and Prx-8 and -9, together with 10 polymorphic putative loci. Analysis of cosegregations of the segregating loci with each other, and with loci established previously, resulted in 19 more loci being added to the cherry linkage map. Fifteen of these were new, and four had been described previously, but were hitherto unlinked. The additional linkages are: Ara-1– Dia-2– Mdh-2–Est-2; Glu-3/Prx-8–Glu-1/-2/-4–Prx-1/-9; Pgd-2–Pho-1/-2; Idh-2–Est-7–Est-6; (Amy-2)–Est-1–(Adh-4/-6); and (Acp-1/-2/-3)–Hex-1–(Gpi-2). (The bracketed loci had been mapped already). Several cherry linkages resemble linkages reported in apple. Analysis of 14 cultivars of P. avium for the same enzyme systems revealed polymorphism for just four of the 15 loci, and for an additional putative locus that was monomorphic in the interspecific material. This lack of isoenzyme polymorphism among cherry cultivars reduces the utility of these markers for linkage analysis and mapping in progenies of P. avium. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

13.
X. Q. Zhang    X. P. Wang    J.K. Jing    K. Ross    H. Hu    J. P. Gustafson   《Plant Breeding》1998,117(1):7-12
Five wheat-triticale doubled haploid (DH) lines— M08, V209, DH220-14-2, DH696-3-4 and M16 —derived from anther culture of F1s resulting from crosses involving hexaploid or octoploid triticale × hexaploid wheat, were characterized by cytological and biochemical markers. Cytological evidence from genomic in situ hybridization and C-banding indicated that DH lines M08 and V209 (2n= 42) each contained a pair of 1BL/1RS translocation chromosomes. DH220-14-2 (2n= 42) was also a translocated line with two pairs of chromosomes containing small fragments of rye. One of the translocation fragments carried the Sec-1R gene originating from the satellite region of 1RS; the origin of the other one remains unknown. DH696-3-4 (2n= 42) contained a 3D(3R) substitution. In M16 (2n= 44), three pairs of rye chromosomes, 3R, 4R and 6R, were present, 4R as an addition and 3D(3R) and 6D(6R) as substitutions. Biochemical, isozyme and storage protein markers confirmed the cytological conclusions. The advantages of transferring alien chromosomes or chromosome fragments into wheat and creating alien aneuploid lines by anther culture of hybrid F1s are discussed.  相似文献   

14.
不同水稻品种对褐飞虱的耐虫特性研究   总被引:3,自引:0,他引:3  
褐飞虱是中国水稻生产上最主要的害虫之一,以褐飞虱的耐虫性指数和抗生性指数以及F1代种群繁殖率评价10个水稻品种耐虫特性。结果显示,在水稻三叶期接入8头褐飞虱低龄(1~2龄)若虫为害时,品种间的耐虫性差异明显,汕优63、秀水11、培矮64S/32E、Triveni、Utri Rajapan、嘉育948、ASD7等品种的耐虫指数大于抗生性指数,尤其是汕优63品种;而IR64、Rathu Heenati品种的耐虫指数明显小于抗生性指数。若用高龄(3~4龄)若虫为害,多数品种的耐虫指数上升。同一品种,成株期的耐虫指数高于苗期。试验进一步表明,当TN1、秀水11稻株枯死时,汕优63、培矮64S/E32、嘉育948、Triveni、Utri Rajapan中等受害,ASD7和IR64轻度受害,Rathu Heenati无受害症状。从褐飞虱F1代数量来看,汕优63、培矮64S/E32与秀水11、TN1无显著差异,且均高于其他品种;嘉育948、Triveni、Utri Rajapan显著高于ASD7,后者又极显著高于IR64和Rathu Heenati。这些结果表明,汕优63、秀水11、TN1属感虫品种,无耐虫性和抗生性,培矮64S/E32、Triveni、Utri Rajapan属强耐虫性品种,IR64、Rathu Heenati属强抗生性品种,ASD7、嘉育948属耐虫性较强、抗生性较弱的品种。说明利用本文的评价方法基本上可以确定水稻品种的耐虫特性,这对耐虫品种的选育以及对褐飞虱可持续治理和保持品种抗性的稳定有着重要的现实意义。  相似文献   

15.
甘蓝品种的AFLP指纹鉴别图谱分析   总被引:1,自引:0,他引:1  
本试验采用AFLP技术分析了来自全国9个栽培地区的44个甘蓝主栽品种,共筛选了40对E 3/M 3引物组合,多态性条带的数量从0条到15条不等。其中引物组合E-AAC/M-CTA是甘蓝品种中多态性最高的引物,有15条多态性条带,多态性条带的百分率为30%,但该引物不足以区分44个供试的甘蓝品种。同时筛选了11组E 2/M 3对引物组合,其中引物组合E-AG/M-CTC产生了13条清晰的多态性条带。以E-AAC/M-CTA和E-AG/M-CTC这两对引物组合的多态性条带构建了44份甘蓝品种材料的指纹图谱,此指纹图谱可以将供试的44份材料一一区分。  相似文献   

16.
Summary Phenotypic variation for parameters of seed yield were examined in 57 buffalo gourd (Cucurbita foetidissima HBK.) plants cultivated as annuals. Among the 52 individuals which bore fruit, seed weight/plant was highly variable (cv=106%); the majority of plants exhibited seed yields below that of the mean (431 g/plant). Values of seed weight/plant were more highly influenced by fruit/plant (r=+0.81) than by seed weight/fruit (r=+0.19). Variation in fruit/plant % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGak0dh9WrFfpC0xh9vqqj-hEeeu0xXdbba9frFj0-OqFf% ea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs0dXdbPYxe9vr0-vr% 0-vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOqaaiaacIcaceWG4b% GbaebacqGH9aqpcaaIYaGaaGimaiaaicdacaqGNbGaae4oaiaabcca% caqGJbGaaeODaiaabccacaqG9aGaaeiiaiaabodacaqG3aGaaeyjai% aabMcaaaa!454B!\[(\bar x = 56; cv = 115\% )\] was greater than that displayed for seed weight/fruit and their distribution was also highly skewed. High fruit yields were associated with the duration (in nodes) of the fruiting period (r=+0.64).Values for seed weight/fruit were also highly divergent % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGak0dh9WrFfpC0xh9vqqj-hEeeu0xXdbba9frFj0-OqFf% ea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs0dXdbPYxe9vr0-vr% 0-vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOqaaiaacIcaceWG4b% GbaebacqGH9aqpcaaIYaGaaGimaiaaicdacaqGNbGaae4oaiaabcca% caqGJbGaaeODaiaabccacaqG9aGaaeiiaiaabodacaqG3aGaaeyjai% aabMcaaaa!454B!\[(\bar x = 200{\text{g; cv = 37\% )}}\], but considerably less variable than those for fruit/plant or seed weight/plant. A weak relationship existed between fruit/plant and seed weight/fruit (r=–0.28), suggesting the possibility of their simultaneous improvement through selection. Seed weight/fruit was positively associated with fruit size, seed/fruit and 100-seed weight; 4 carpellate fruit displayed significantly greater seed weight/fruit and seed/fruit than 3 carpellate fruit.Journal Paper No. 4219 of the University of Arizona Agric. Expt. Sta., Tucson, AZ 85721, U.S.A.  相似文献   

17.
按Griffing双列杂交方法Ⅳ,对9个热带和温带玉米群体进行组配,获得36个杂交组合。2002年和2003年,采用混合线性(AD)模型和最小范数二阶无偏估算法(1)法(minimum norm quadratic unbiased estimation, MINQUE),分别在河南安阳和湖北十堰进行田间鉴定,对产量和产量构成因素的遗传方差分量、杂交组合的基因型值进行了分析。结果显示,产量和产量构成因素的遗传方差分量及其与环境的互作效应大多达到极显著水平,但各项遗传方差分量对总表型变异的贡献有差异。对小区产量而言,各效应的贡献是显性>显性与环境互作>加性与环境互作>加性;而加性方差分量对总表型变异的贡献为穗行数>穗粒数>百粒重>小区产量。对这36个组合的群体平均优势和群体超亲优势进行了估计,并在此基础上引入群体间遗传差异的度量参数ω/(2μ),ω/(2μ) = 群体平均优势-群体超亲优势。对9个群体的比较表明,遗传差异与杂种优势之间不存在线性关系,亲本的遗传差异过大和过小都不利于产生强优势组合,具有中等遗传差异的亲本群体表现出了强的杂种优势。如组合3´6 (BSSS C9´Stay Green C4)、2´3 (BS16´BSSS C9)和1´3 (Suwan1´BSSS C9)都具有中等的遗传差别,有较好的杂种优势表现;BSSS C9与Stay Green C4和Suwan1、BS16和Suwan1在温带育种中值得关注,有可能形成新的杂种优势模式。  相似文献   

18.
Hempseed as a nutritional resource: An overview   总被引:7,自引:0,他引:7  
J. C. Callaway 《Euphytica》2004,140(1-2):65-72
Summary The seed of Cannabis sativa L. has been an important source of nutrition for thousands of years in Old World cultures. Non-drug varieties of Cannabis, commonly referred to as hemp, have not been studied extensively for their nutritional potential in recent years, nor has hempseed been utilized to any great extent by the industrial processes and food markets that have developed during the 20th century. Technically a nut, hempseed typically contains over 30% oil and about 25% protein, with considerable amounts of dietary fiber, vitamins and minerals. Hempseed oil is over 80% in polyunsaturated fatty acids (PUFAs), and is an exceptionally rich source of the two essential fatty acids (EFAs) linoleic acid (18:2 omega-6) and alpha-linolenic acid (18:3 omega-3). The omega-6 to omega-3 ratio (n6/n3) in hempseed oil is normally between 2:1 and 3:1, which is considered to be optimal for human health. In addition, the biological metabolites of the two EFAs, gamma-linolenic acid (18:3 omega-6; GLA) and stearidonic acid (18:4 omega-3; SDA), are also present in hempseed oil. The two main proteins in hempseed are edestin and albumin. Both of these high-quality storage proteins are easily digested and contain nutritionally significant amounts of all essential amino acids. In addition, hempseed has exceptionally high levels of the amino acid arginine. Hempseed has been used to treat various disorders for thousands of years in traditional oriental medicine. Recent clinical trials have identified hempseed oil as a functional food, and animal feeding studies demonstrate the long-standing utility of hempseed as an important food resource.  相似文献   

19.
'Laiyang Chili’ and ‘Ya Li’ (Pyrus bertschneideri Reld) pears were treated with 3, 6, and 9% emulsions of commercial or refined (reduced -tocopherol levels) plant (soybean, corn, peanut, linseed, and cottonseed) oils at harvest an stored at 0°C for 6 months. Effects of oil treatments on ethylene production, respiration, fruit firmness, fruit color, soluble solid content (SSC), titratable acids (TA), internal browning (IB), and internal CO2, O2, and ethanol were studied. At the same concentration, oil treatments induced similar responses regardless of their sources or their -tocopherol concentrations. In both cultivars, ethylene production and respiration in fruit treated with 9% oils were lower in early storage and higher in late storage than that in the controls. Oils at 6% reduced IB, at 9% inhibited IB completely, and at 3% was not effective after 6 months at 0°C and 7 days at 20°C. Plant oil treatment maintained fruit color, firmness, SSC, and TA in a concentration-dependent manner during storage. In the first 4 months storage, 9% corn oil-treated fruit contained similar partial pressure of CO2 and O2 as the controls. After 5 months storage, oil-treated fruit contained higher partial pressure of CO2 and lower levels of O2 than the controls. When held at 20°C for 7 days, changes of internal CO2 and O2 were slower but partial pressure of CO2 were higher, and O2 were lower, in 9% corn oil-treated fruit than in the controls. Internal ethanol was not affected by oil treatment compared with control, either during storage or 7 days at 20°C. No off-flavor was detected in either oil-treated and control fruit by sensory evaluation.  相似文献   

20.
The principle and possibility of alloying of high speed steel W6Mo5Cr4V2 (M2) with CaWO 4 MoO 3 V 2O 5 during the steelmaking are discussed, experiments of the alloying technologcial process have been carried out, the properties of M2 product have been determined, the benefit have been analysed. The results show that the rate of recovery of W Mo V are respectively 97.08%, 96.51%, 93.79% during the steelmaking of M2 alloying with CaWO 4 MoO 3 V 2O 5 in induction furnace, the chemical composition and properties of product M2 can meet the demands that the standard of high speed steel M2 requires.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号