合成了酚氧基邻位上含有大位阻基团的双[(N-3,5-二枯基亚水杨醛)-2’-甲基环己胺]二氯化锆催化剂(Cat),并将其应用于乙烯均聚制备超高分子量聚乙烯(UHMWPE)。研究了以甲苯为溶剂,不同助催化剂、n(Al)/n(Zr)、聚合时间、聚合温度条件下,...合成了酚氧基邻位上含有大位阻基团的双[(N-3,5-二枯基亚水杨醛)-2’-甲基环己胺]二氯化锆催化剂(Cat),并将其应用于乙烯均聚制备超高分子量聚乙烯(UHMWPE)。研究了以甲苯为溶剂,不同助催化剂、n(Al)/n(Zr)、聚合时间、聚合温度条件下,对Cat催化乙烯的聚合活性、UHMWPE相对分子质量的影响。结果表明,Cat在以甲基铝氧烷(MAO)或烷基铝为助催化剂,n(Al)/n(Zr)=50000,聚合时间为2h,聚合温度为50℃的条件下可高效催化乙烯聚合获得UHMWPE,催化活性大于200×10~6 g PE/mol Zr;尤其在三甲基铝(TMA)助催化剂的存在下,可获得黏均相对分子质量达到8×10~6的UHMWPE。展开更多
Five different trapping treatments, spraying attractant on bottle surface and spraying attractant inside the bottles with 0, 50,100 and 200 mL water, were set to trap Bactrocera dorsalis and B. cucurbitae in guava （P...Five different trapping treatments, spraying attractant on bottle surface and spraying attractant inside the bottles with 0, 50,100 and 200 mL water, were set to trap Bactrocera dorsalis and B. cucurbitae in guava （Psidium guajava） park. The results showed that when the usage of attractant was 1 g, both Haonian and Wende had trapping effect on B. dorsalis and B. cucurbitae. The trapping effect of Haonian on B. dorsalis was better than that of Wende, while their trapping effects on B. cucurbitae was just the opposite. The trapping effects of different treatments had great difference. The trapping effect of Haonian on two species of fruit flies enhanced with the increasing volume of water, and reached the ma^mum value as the water volume was 200 mL. With the increasing volume of water, the trap- ping effect of Wende on two species of fruit flies first increased, and then decreased, which reached the maximum value as the water volume was 50 mL. Different treatments with attractants spraying inside bottles had better trapping effects on two species of fruit flies than that spraying on bottle surface.展开更多
The Yangla Copper Ore Field in Northwest Yunnan Province, China, is a large region of deposits dominated by copper-bearing skarns whose origin remains debatable despite numerous studies over the past two decades. We h...The Yangla Copper Ore Field in Northwest Yunnan Province, China, is a large region of deposits dominated by copper-bearing skarns whose origin remains debatable despite numerous studies over the past two decades. We have investigated the geological and geochemical characteristics of the skarns using field and microscopic observations combined with chemical analyses. The results show that the skarns fall into two categories. The first category is metamorphic skarn, which constitute the majority （〉90%） of skarns in the deposit and is characterized by stratiform occurrences conformable to Devonian host strata, anhydrous mineral assemblages such as diopside＋hedenbergite＋quartz, widespread banded structure, fine-grainsize （〈200 μm） and preserved tuff-like textures. Whole-rock major element compositions, REE and trace-element compositions resemble those of the country rock slates or schists. The skarn layers occur at variable distances （0-2 000 m） from Indosinian plutonic bodies. Fracture-filling veins and/or alteration halos are scarce or absent in or near the skarn layers. This category of skarn probably formed by isochemical contact metamorphism of fine calcareous clastic sediments or impure carbonate rocks during emplacement of the plutonic bodies with no significant material migration by hydrothermal fluids involved during the process, in which case metallic enrichment of the skarn layers was present in the protolith of the skarn. The second category is metasomatic skarn with relatively coarse-grained textures （200-〉1 000 μm） and volatile-reach assemblages such as diopside＋tremolite＋scapolite at or near the igneous contact zones, which constitutes only a minor pro-portion of ore compared with metamorphic skarn. Taking into consideration diverse existing opinions about the genetic type of the deposit, we suggest that the geological and whole-rock geochemical characteristics of the skarus are consistent with a metamorphosed and metasomatized SEDEX （sedimentary exhalative deposit） type rather than a hydrothermal metasomatic skarn type.展开更多
文摘合成了酚氧基邻位上含有大位阻基团的双[(N-3,5-二枯基亚水杨醛)-2’-甲基环己胺]二氯化锆催化剂(Cat),并将其应用于乙烯均聚制备超高分子量聚乙烯(UHMWPE)。研究了以甲苯为溶剂,不同助催化剂、n(Al)/n(Zr)、聚合时间、聚合温度条件下,对Cat催化乙烯的聚合活性、UHMWPE相对分子质量的影响。结果表明,Cat在以甲基铝氧烷(MAO)或烷基铝为助催化剂,n(Al)/n(Zr)=50000,聚合时间为2h,聚合温度为50℃的条件下可高效催化乙烯聚合获得UHMWPE,催化活性大于200×10~6 g PE/mol Zr;尤其在三甲基铝(TMA)助催化剂的存在下,可获得黏均相对分子质量达到8×10~6的UHMWPE。
基金Supported by Special Fund for Agro-scientific Research in the Public Interest( 201103026-1)
文摘Five different trapping treatments, spraying attractant on bottle surface and spraying attractant inside the bottles with 0, 50,100 and 200 mL water, were set to trap Bactrocera dorsalis and B. cucurbitae in guava （Psidium guajava） park. The results showed that when the usage of attractant was 1 g, both Haonian and Wende had trapping effect on B. dorsalis and B. cucurbitae. The trapping effect of Haonian on B. dorsalis was better than that of Wende, while their trapping effects on B. cucurbitae was just the opposite. The trapping effects of different treatments had great difference. The trapping effect of Haonian on two species of fruit flies enhanced with the increasing volume of water, and reached the ma^mum value as the water volume was 200 mL. With the increasing volume of water, the trap- ping effect of Wende on two species of fruit flies first increased, and then decreased, which reached the maximum value as the water volume was 50 mL. Different treatments with attractants spraying inside bottles had better trapping effects on two species of fruit flies than that spraying on bottle surface.
基金financially supported by the China Geological Survey(No.12120113079400)
文摘The Yangla Copper Ore Field in Northwest Yunnan Province, China, is a large region of deposits dominated by copper-bearing skarns whose origin remains debatable despite numerous studies over the past two decades. We have investigated the geological and geochemical characteristics of the skarns using field and microscopic observations combined with chemical analyses. The results show that the skarns fall into two categories. The first category is metamorphic skarn, which constitute the majority （〉90%） of skarns in the deposit and is characterized by stratiform occurrences conformable to Devonian host strata, anhydrous mineral assemblages such as diopside＋hedenbergite＋quartz, widespread banded structure, fine-grainsize （〈200 μm） and preserved tuff-like textures. Whole-rock major element compositions, REE and trace-element compositions resemble those of the country rock slates or schists. The skarn layers occur at variable distances （0-2 000 m） from Indosinian plutonic bodies. Fracture-filling veins and/or alteration halos are scarce or absent in or near the skarn layers. This category of skarn probably formed by isochemical contact metamorphism of fine calcareous clastic sediments or impure carbonate rocks during emplacement of the plutonic bodies with no significant material migration by hydrothermal fluids involved during the process, in which case metallic enrichment of the skarn layers was present in the protolith of the skarn. The second category is metasomatic skarn with relatively coarse-grained textures （200-〉1 000 μm） and volatile-reach assemblages such as diopside＋tremolite＋scapolite at or near the igneous contact zones, which constitutes only a minor pro-portion of ore compared with metamorphic skarn. Taking into consideration diverse existing opinions about the genetic type of the deposit, we suggest that the geological and whole-rock geochemical characteristics of the skarus are consistent with a metamorphosed and metasomatized SEDEX （sedimentary exhalative deposit） type rather than a hydrothermal metasomatic skarn type.
