摘要:
Disclosed herein are a method for preparing a cis-1,4-polybutadiene with a controlled molecular weight distribution, comprising polymerizing butadiene monomers using a rare-earth catalyst system comprising: (a) at least one aliphatic hydrocarbon-soluble organometallic compound comprising at least one metal element chosen from the elements of atomic numbers 51-71 in the periodic table; (b) at least one organoaluminum compound of the formula: AlR1R22, (c) at least one aliphatic hydrocarbon-soluble halogen-containing compound; (d) optionally at least one alkylaluminum alkoxide; and (e) at least one conjugated double bond-containing organic compound, and methods of preparing the rare-earth catalyst system.
摘要:
A system and method are provided for identifying exposure concentrations. The process of determining exposure concentrations may include organizing exposure data, defining parameters, determining elevated exposure concentrations, and providing output results. The exposure data may relate to at least geographical locations, policies, accounts, portfolios, treaties, and other exposure data. The parameters may be defined to include at least an area of analysis, a region of interest, a threshold amount, results parameters, and other parameters. The exposure concentration may include at least defining and locating exposure locations using various techniques. The results may be presented using textual, graphical, or other display schemes. The output may be configured to convey information such as positional accuracy of an identified area, exposure accumulation in a defined area, and other information.
摘要:
A method of minimizing stress within large area semiconductor devices which utilize a GaAs substrate and one or more thick layers of AlxGa1-xAs is provided, as well as the resultant device. In general, each thick AlxGa1-xAs layer within the semiconductor structure is replaced, during the structure's fabrication, with an AlxGa1-xAszP1-z layer of approximately the same thickness and with the same concentrations of Al and Ga. The AlxGa1-xAszP1-z layer is lattice matched to the GaAs substrate by replacing a small percentage of the As in the layer with P.
摘要翻译:提供了利用GaAs衬底和一个或多个厚层的Al x Ga 1-x As As的大面积半导体器件内的应力最小化的方法,以及 结果装置。 通常,半导体结构中的每个厚的Al x Al x Ga 1-x O As层在结构的制造期间被替换为Al x 大约相同厚度和相同浓度的Al和Ga的Ga 1-x S 1 z z 1 1 z z层,Al < 通过代替小的GaN层,与GaN衬底晶格匹配, As在与P的层中的百分比
摘要:
A system and method are provided for identifying exposure concentrations. The process of determining exposure concentrations may include organizing exposure data, defining parameters, determining elevated exposure concentrations, and providing output results. The exposure data may relate to at least geographical locations, policies, accounts, portfolios, treaties, and other exposure data. The parameters may be defined to include at least an area of analysis, a region of interest, a threshold amount, results parameters, and other parameters. The exposure concentration may include at least defining and locating exposure locations using various techniques. The results may be presented using textual, graphical, or other display schemes. The output may be configured to convey information such as positional accuracy of an identified area, exposure accumulation in a defined area, and other information.
摘要:
A system and method are provided for identifying exposure concentrations. The process of determining exposure concentrations may include organizing exposure data, defining parameters, determining elevated exposure concentrations, and providing output results. The exposure data may relate to at least geographical locations, policies, accounts, portfolios, treaties, and other exposure data. The parameters may be defined to include at least an area of analysis, a region of interest, a threshold amount, results parameters, and other parameters. The exposure concentration may include at least defining and locating exposure locations using various techniques. The results may be presented using textual, graphical, or other display schemes. The output may be configured to convey information such as positional accuracy of an identified area, exposure accumulation in a defined area, and other information.
摘要:
A semiconductor laser and a method of forming the same are provided. The n-side and p-side junctions are independently optimized to improve carrier flow. The material for the n-side cladding layer is selected to yield a small conduction to valance band gap offset ratio while the material for the p-side cladding layer is selected to yield a large conduction to valance band gap offset ratio.
摘要:
The present invention relates to a catalyst for synthesizing a polypropylene with a wide molecular weight distribution and use of the same. The catalyst comprises magnesium halide, titanium-containing compound, and an organic phosphate type electron donor compound. By the catalyst according to the present invention, a propylene polymer with a wide molecular weight distribution, easily controllable isotacticity and good processing properties can be synthesized.
摘要:
A system and method are provided for identifying exposure concentrations. The process of determining exposure concentrations may include organizing exposure data, defining parameters, determining elevated exposure concentrations, and providing output results. The exposure data may relate to at least geographical locations, policies, accounts, portfolios, treaties, and other exposure data. The parameters may be defined to include at least an area of analysis, a region of interest, a threshold amount, results parameters, and other parameters. The exposure concentration may include at least defining and locating exposure locations using various techniques. The results may be presented using textual, graphical, or other display schemes. The output may be configured to convey information such as positional accuracy of an identified area, exposure accumulation in a defined area, and other information.
摘要:
The present invention relates to a catalyst for synthesizing a polypropylene with a wide molecular weight distribution and use of the same. The catalyst comprises magnesium halide, titanium-containing compound, and an organic phosphate type electron donor compound. By the catalyst according to the present invention, a propylene polymer with a wide molecular weight distribution, easily controllable isotacticity and good processing properties can be synthesized.
摘要:
A means of controlling the stress in a laser diode structure through the use of AlGaAsP is provided. Depending upon the amount of phosphorous in the material, it can be used to either match the lattice constant of GaAs, thus forming a strainless structure, or mismatch the lattice constant of GaAs, thereby adding tensile stress to the structure. Tensile stress can be used to mitigate the compressive stress due to material mismatches within the structure (e.g., a highly strained compressive quantum well), or due to the heat sink bonding procedure.