High-temperature and high-salt reservoirs are often accompanied by serious gas channeling in gas flooding,which will greatly affect the effect of gas injection development,so in-situ foaming of temperature-resistant a...High-temperature and high-salt reservoirs are often accompanied by serious gas channeling in gas flooding,which will greatly affect the effect of gas injection development,so in-situ foaming of temperature-resistant and salt-resistant foaming agents is commonly used to control gas channeling.The feasibility of the compound system of dodecyl hydroxyl sulfobetaine(HSB12)andα-olefin sulfonate(AOS)as foaming agent for sandstone reservoir was studied at 130℃and 22×10^(4)mg/L.The results showed that the foaming agent(HSB12 and AOS were compounded in a 6:1 mass ratio,in this article,this foaming agent is simply referred to as SA61)had good solubility in 22×10^(4)mg/L simulated formation water.Besides,the foaming volume of SA61 and HSB12 was similar,but the foam decay half-life of SA61was 10-25 times higher than that of HSB12.The foaming performance of SA61 on the surface of quartz sand remained above 90%of that before adsorption.The strong interaction between HSB12 and AOS in the compound system SA61 was demonstrated by surface rheological measurements and NMR studies of surfactants.The results of co re flow test showed that SA61 had better mobility control ability than HSB12under the same surfactant concentration.In addition,SA61 showed a selective mobility reduction in2005.30 and 632.00 mD cores.The above research results can guide the selection and application of foaming agent in clastic reservoir.展开更多
Objective:To explore the effect of TCD foaming test in screening patent foramen ovale in migraine patients,as well as in the treatment effect.Methods:From September 2019 to August 2020,236 patients with migraine and 3...Objective:To explore the effect of TCD foaming test in screening patent foramen ovale in migraine patients,as well as in the treatment effect.Methods:From September 2019 to August 2020,236 patients with migraine and 362 patients with normal physical examination were treated in our hospital.According to the random number table method,60 patients with migraine were selected as the observation group,and 60 patients with normal physical examination were selected as the control group.48 cases of PFO were confirmed by TCD foaming test Among the patients with migraine,36 patients received interventional occlusion therapy.The therapeutic effect and VAS score of the two groups were analyzed.Results:Through TCD foaming test,the proportion of PFO in the observation group was 80%,and that in the control group was 13.33%.The proportion of PFO in the observation group was significantly higher than that in the control group,and the difference was statistically significant(χ^(2)=53.5714,P<0.01);The symptoms disappeared in 30 patients and improved in 4 patients;Among the 36 patients who received interventional occlusion therapy,the VAS score of patients before and after the operation was significantly changed,and the proportion of patients whose pain disappeared after the operation was 83.33%,which was significantly lower than that before the operation,and the difference was comparable(χ^(2)=51.4286,P<0.01).Conclusion:TCD foaming test for PFO screening has strong applicability,not only safe and convenient,will not cause trauma to patients,and through interventional occlusion treatment,can significantly improve the clinical symptoms of migraine patients and cure patients.展开更多
光学电流互感器具有测量精度高、结构简单、安全性高等特点,其关键组件光纤复合绝缘子承担着通信和电气绝缘的双重作用。然而,现有不同光纤植入型式的光纤复合绝缘子芯体存在相应材料、结构或工艺等缺陷,光纤与绝缘材料之间易产生界面隐...光学电流互感器具有测量精度高、结构简单、安全性高等特点,其关键组件光纤复合绝缘子承担着通信和电气绝缘的双重作用。然而,现有不同光纤植入型式的光纤复合绝缘子芯体存在相应材料、结构或工艺等缺陷,光纤与绝缘材料之间易产生界面隐患,威胁电气设备安全运行。该文提出采用低密度环氧基复合泡沫作为光纤芯体基体,植入聚乙烯型低烟无卤(low smoke zero halogen polyethylene,LSZHPE)、聚乙烯-四氟乙烯(ethylene-tetrafluoroethylene copolymer,ETFE)及裸纤3种光纤,对比分析不同类型光纤芯体物理、界面、电气等关键性能。结果表明:LSZHPE光纤体系芯体具有较优的综合性能,150 h水扩散泄漏电流低于100μA,界面击穿强度达到13.34 k V/mm,同时光纤植入后光导通损耗满足实际应用要求;ETFE光纤及裸纤体系芯体电气性能良好,但受限于材料自身特性,界面剪切强度较低,界面可靠性相对较差。该研究为光纤复合绝缘子材料选型、界面评估及结构优化提供了新思路。展开更多
Composite sandwich structures are highly proven materials that provide high strength to weight ratio. However research works are still being carried out in the area of impact characteristics of sandwich composites. Th...Composite sandwich structures are highly proven materials that provide high strength to weight ratio. However research works are still being carried out in the area of impact characteristics of sandwich composites. This paper provides a better understanding on the effect of core density and core thickness of sandwich panels subject to low velocity drop test. Specific energy absorption capacity of sandwich panels is obtained and factors affecting the same are explored with facings made of woven glass fiber laminates and polyurethane foam core with three different densities of 70 Kg/m3, 100 Kg/m3, 200 Kg/m3.展开更多
Recently, a large amount of circulating fluidized bed boiler ash (CFBA) and desulfurization gypsum (DSG) has been produced, and it is essential to develop technology to utilize them. These materials have CaO and SO<...Recently, a large amount of circulating fluidized bed boiler ash (CFBA) and desulfurization gypsum (DSG) has been produced, and it is essential to develop technology to utilize them. These materials have CaO and SO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, which </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">are</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> considered to be a stimulant for blast furnace slag (BFS). This study presents an experimental investigation of the compressive strength and heavy metal ions immobilization properties of cement-free materials comprising CFBA, BFS, and DSG. The feasibility of manufacturing foamed concrete using these materials was examined, and field test of foamed concrete was conducted. Experimentally, the flow, compressive strength, and heavy metal ions concentration were evaluated via inductively coupled plasma atomic emission spectroscopy (ICP</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">AES) of the paste and foamed concrete. The experimental investigation revealed the self-healing hardening ability of fluidized bed boiler ash. In addition, the compressive strength was increased with the increasing replacement rates of BFS and DSG in the CFBA paste, and the compressive strength of 14.6</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> - </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">17.2 MPa was recorded over 28 days of curing. From the result obtained, the feasibility of manufacturing foamed concrete with a foam volume </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">120 L, incorporating the aforementioned materials, is confirmed. It was also found that after 28 days of age, a 7.9-MPa compressive strength of the foamed concrete was attained, and heavy metal ions elution in this foamed concrete was also significantly reduced. Therefore, CFBA, BFS, and DSG could be used as a binder for the foamed concrete.展开更多
基金financial support from the Major Scientific and Technological Projects of CNPC(Award No.ZD2019-183-007)。
文摘High-temperature and high-salt reservoirs are often accompanied by serious gas channeling in gas flooding,which will greatly affect the effect of gas injection development,so in-situ foaming of temperature-resistant and salt-resistant foaming agents is commonly used to control gas channeling.The feasibility of the compound system of dodecyl hydroxyl sulfobetaine(HSB12)andα-olefin sulfonate(AOS)as foaming agent for sandstone reservoir was studied at 130℃and 22×10^(4)mg/L.The results showed that the foaming agent(HSB12 and AOS were compounded in a 6:1 mass ratio,in this article,this foaming agent is simply referred to as SA61)had good solubility in 22×10^(4)mg/L simulated formation water.Besides,the foaming volume of SA61 and HSB12 was similar,but the foam decay half-life of SA61was 10-25 times higher than that of HSB12.The foaming performance of SA61 on the surface of quartz sand remained above 90%of that before adsorption.The strong interaction between HSB12 and AOS in the compound system SA61 was demonstrated by surface rheological measurements and NMR studies of surfactants.The results of co re flow test showed that SA61 had better mobility control ability than HSB12under the same surfactant concentration.In addition,SA61 showed a selective mobility reduction in2005.30 and 632.00 mD cores.The above research results can guide the selection and application of foaming agent in clastic reservoir.
文摘Objective:To explore the effect of TCD foaming test in screening patent foramen ovale in migraine patients,as well as in the treatment effect.Methods:From September 2019 to August 2020,236 patients with migraine and 362 patients with normal physical examination were treated in our hospital.According to the random number table method,60 patients with migraine were selected as the observation group,and 60 patients with normal physical examination were selected as the control group.48 cases of PFO were confirmed by TCD foaming test Among the patients with migraine,36 patients received interventional occlusion therapy.The therapeutic effect and VAS score of the two groups were analyzed.Results:Through TCD foaming test,the proportion of PFO in the observation group was 80%,and that in the control group was 13.33%.The proportion of PFO in the observation group was significantly higher than that in the control group,and the difference was statistically significant(χ^(2)=53.5714,P<0.01);The symptoms disappeared in 30 patients and improved in 4 patients;Among the 36 patients who received interventional occlusion therapy,the VAS score of patients before and after the operation was significantly changed,and the proportion of patients whose pain disappeared after the operation was 83.33%,which was significantly lower than that before the operation,and the difference was comparable(χ^(2)=51.4286,P<0.01).Conclusion:TCD foaming test for PFO screening has strong applicability,not only safe and convenient,will not cause trauma to patients,and through interventional occlusion treatment,can significantly improve the clinical symptoms of migraine patients and cure patients.
文摘光学电流互感器具有测量精度高、结构简单、安全性高等特点,其关键组件光纤复合绝缘子承担着通信和电气绝缘的双重作用。然而,现有不同光纤植入型式的光纤复合绝缘子芯体存在相应材料、结构或工艺等缺陷,光纤与绝缘材料之间易产生界面隐患,威胁电气设备安全运行。该文提出采用低密度环氧基复合泡沫作为光纤芯体基体,植入聚乙烯型低烟无卤(low smoke zero halogen polyethylene,LSZHPE)、聚乙烯-四氟乙烯(ethylene-tetrafluoroethylene copolymer,ETFE)及裸纤3种光纤,对比分析不同类型光纤芯体物理、界面、电气等关键性能。结果表明:LSZHPE光纤体系芯体具有较优的综合性能,150 h水扩散泄漏电流低于100μA,界面击穿强度达到13.34 k V/mm,同时光纤植入后光导通损耗满足实际应用要求;ETFE光纤及裸纤体系芯体电气性能良好,但受限于材料自身特性,界面剪切强度较低,界面可靠性相对较差。该研究为光纤复合绝缘子材料选型、界面评估及结构优化提供了新思路。
文摘Composite sandwich structures are highly proven materials that provide high strength to weight ratio. However research works are still being carried out in the area of impact characteristics of sandwich composites. This paper provides a better understanding on the effect of core density and core thickness of sandwich panels subject to low velocity drop test. Specific energy absorption capacity of sandwich panels is obtained and factors affecting the same are explored with facings made of woven glass fiber laminates and polyurethane foam core with three different densities of 70 Kg/m3, 100 Kg/m3, 200 Kg/m3.
文摘Recently, a large amount of circulating fluidized bed boiler ash (CFBA) and desulfurization gypsum (DSG) has been produced, and it is essential to develop technology to utilize them. These materials have CaO and SO</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, which </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">are</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> considered to be a stimulant for blast furnace slag (BFS). This study presents an experimental investigation of the compressive strength and heavy metal ions immobilization properties of cement-free materials comprising CFBA, BFS, and DSG. The feasibility of manufacturing foamed concrete using these materials was examined, and field test of foamed concrete was conducted. Experimentally, the flow, compressive strength, and heavy metal ions concentration were evaluated via inductively coupled plasma atomic emission spectroscopy (ICP</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">AES) of the paste and foamed concrete. The experimental investigation revealed the self-healing hardening ability of fluidized bed boiler ash. In addition, the compressive strength was increased with the increasing replacement rates of BFS and DSG in the CFBA paste, and the compressive strength of 14.6</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> - </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">17.2 MPa was recorded over 28 days of curing. From the result obtained, the feasibility of manufacturing foamed concrete with a foam volume </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">120 L, incorporating the aforementioned materials, is confirmed. It was also found that after 28 days of age, a 7.9-MPa compressive strength of the foamed concrete was attained, and heavy metal ions elution in this foamed concrete was also significantly reduced. Therefore, CFBA, BFS, and DSG could be used as a binder for the foamed concrete.
