为了准确测量油藏条件下气体、液体和气液混合物的运移黏度,依据泊肃叶定律设计了毛细管黏度计。毛细管黏度计主要包括注入系统、测量系统、回压控制系统和辅助系统4个部分。针对气体、液体和气液混合物的特性,分别设计了气体注入系统...为了准确测量油藏条件下气体、液体和气液混合物的运移黏度,依据泊肃叶定律设计了毛细管黏度计。毛细管黏度计主要包括注入系统、测量系统、回压控制系统和辅助系统4个部分。针对气体、液体和气液混合物的特性,分别设计了气体注入系统、液体注入系统和气液混合注入系统,并研制了不同内径的毛细管和不同渗透率的孔隙介质模型模拟油藏孔隙。结果表明,毛细管黏度计实现了气体、液体和气液混合物的注入速度准确计量和黏度测量,回压控制系统采用回压式位移量化控制系统精准控制回压,提高了毛细管黏度计测量的准确度和精度。在模拟油藏条件氮气黏度非常低,仅为0.018 mPa·s,而聚合物和泡沫体系毛细管黏度较高,分别为78 m Pa·s和126 m Pa·s。展开更多
Backgroud Numerous studies have confirmed the effectiveness of slowing the progression of atherosclerosis by blood pressure （Bp） control in patients with hypertension and several studies also showed the efficacy of ...Backgroud Numerous studies have confirmed the effectiveness of slowing the progression of atherosclerosis by blood pressure （Bp） control in patients with hypertension and several studies also showed the efficacy of intensive glycemic control in decreasing progression of carotid intima-media thickness （CIMT） in patients with type 1 and type 2 diabetes. However, few studies have compared the relative importance of glycemic w＇. Bp control in patients with diabetes and hypertension. We aimed to investigate the association between Bp and glycemic control and subclinical carotid atherosclerosis in older patients with hypertension and type 2 diabetes. Methods In a cross-sectional study, B-mode high-resolution ultrasonography of the carotid artery was performed in 670 subjects （508 males and 162 females） aged 60 years or over who had self-reported hypertension and diabetes but no history of coronary heart disease or stroke. Subjects were categorized by their systolic blood pressure： tight control, 〈 130 mmHg; usual control, 130-139 mmHg; or uncontrolled, 〉 140 mmHg, and by their hemoglobin Alc （HbAlc） level： tight control, 〈 6.5%; usual control, 6.5%-7.5%; or uncontrolled, 〉 7.5%, respectively. Results The mean CIMT was 8.20 ±0.11 mm, and carotid plaque was found in 52.5% （352/670） subjects. Overall, 62.1% of the subjects had subclinical carotid atherosclerosis, defined as having either carotid plaque or elevated CIMT （≥ 1.1 ram）. The mean CIMT was significantly different between Bp control categories （7.60 ± 0.09 mm, 7.90 ±0.08 mm, and 8.60 ± 0.12 mm, respectively, P = 0.03） but not between glycemic control categories （8.20± 0.10 mm, 8.1 ±0.08 mm, and 8.40 ± 0.14 ram, respectively, P = 0.13） using ANCOVA analysis. Multivariable logistic regression adjusting for potential confounding factors showed that usual or uncontrolled Bp control were associated with having carotid plaque （OR = 1.08 and OR=1.42, respectively）, or elevated CIMT [Odd ratio （OR） = 1.17, 95% confidence interval （CI） 1.04-2.24, and OR = 1.54, 95% CI 1.36-2.96, respectively compared to tight Bp control; but did not show glycemic control as independent predictor of either having carotid plaque or elevated CIMT. Conclusions In older patients with hypertension and diabetes, blood pressure control, but not glycemic control is associated with subclinical carotid atherosclerosis.展开更多
The concept and realization process of intelligent compaction for the construction of high roller compacted concrete dam were presented, as well as the theory of monitoring and intelligent feedback control. Based on t...The concept and realization process of intelligent compaction for the construction of high roller compacted concrete dam were presented, as well as the theory of monitoring and intelligent feedback control. Based on the real-time analysis of the compaction index, a multiple regression model of the dam compactness was established and a realime estimation method of compaction quality for the entire work area of roller compacted concrete dam was proposed finally. The adaptive adjustment of the roiling process parameters was achieved, with the speed, the exciting force, the roller pass and the compaction thickness meeting the standards during the whole construction process. As a result, the compaction quality and construction efficiency can be improved. The research provides a new way for the construction quality control of roller compacted concrete dam.展开更多
文摘为了准确测量油藏条件下气体、液体和气液混合物的运移黏度,依据泊肃叶定律设计了毛细管黏度计。毛细管黏度计主要包括注入系统、测量系统、回压控制系统和辅助系统4个部分。针对气体、液体和气液混合物的特性,分别设计了气体注入系统、液体注入系统和气液混合注入系统,并研制了不同内径的毛细管和不同渗透率的孔隙介质模型模拟油藏孔隙。结果表明,毛细管黏度计实现了气体、液体和气液混合物的注入速度准确计量和黏度测量,回压控制系统采用回压式位移量化控制系统精准控制回压,提高了毛细管黏度计测量的准确度和精度。在模拟油藏条件氮气黏度非常低,仅为0.018 mPa·s,而聚合物和泡沫体系毛细管黏度较高,分别为78 m Pa·s和126 m Pa·s。
基金Acknowledgment This research was supported in part by the National Natural Science Foundation of China （81072355）, Beijing Medical Scientific Development Foundation （2007-2039）, Ministry of Science and Technology of China （2009BAI 86B01）.
文摘Backgroud Numerous studies have confirmed the effectiveness of slowing the progression of atherosclerosis by blood pressure （Bp） control in patients with hypertension and several studies also showed the efficacy of intensive glycemic control in decreasing progression of carotid intima-media thickness （CIMT） in patients with type 1 and type 2 diabetes. However, few studies have compared the relative importance of glycemic w＇. Bp control in patients with diabetes and hypertension. We aimed to investigate the association between Bp and glycemic control and subclinical carotid atherosclerosis in older patients with hypertension and type 2 diabetes. Methods In a cross-sectional study, B-mode high-resolution ultrasonography of the carotid artery was performed in 670 subjects （508 males and 162 females） aged 60 years or over who had self-reported hypertension and diabetes but no history of coronary heart disease or stroke. Subjects were categorized by their systolic blood pressure： tight control, 〈 130 mmHg; usual control, 130-139 mmHg; or uncontrolled, 〉 140 mmHg, and by their hemoglobin Alc （HbAlc） level： tight control, 〈 6.5%; usual control, 6.5%-7.5%; or uncontrolled, 〉 7.5%, respectively. Results The mean CIMT was 8.20 ±0.11 mm, and carotid plaque was found in 52.5% （352/670） subjects. Overall, 62.1% of the subjects had subclinical carotid atherosclerosis, defined as having either carotid plaque or elevated CIMT （≥ 1.1 ram）. The mean CIMT was significantly different between Bp control categories （7.60 ± 0.09 mm, 7.90 ±0.08 mm, and 8.60 ± 0.12 mm, respectively, P = 0.03） but not between glycemic control categories （8.20± 0.10 mm, 8.1 ±0.08 mm, and 8.40 ± 0.14 ram, respectively, P = 0.13） using ANCOVA analysis. Multivariable logistic regression adjusting for potential confounding factors showed that usual or uncontrolled Bp control were associated with having carotid plaque （OR = 1.08 and OR=1.42, respectively）, or elevated CIMT [Odd ratio （OR） = 1.17, 95% confidence interval （CI） 1.04-2.24, and OR = 1.54, 95% CI 1.36-2.96, respectively compared to tight Bp control; but did not show glycemic control as independent predictor of either having carotid plaque or elevated CIMT. Conclusions In older patients with hypertension and diabetes, blood pressure control, but not glycemic control is associated with subclinical carotid atherosclerosis.
基金National Natural Science Foundation of China (No. 51021004No. 51079096)the Program for New Century Excellent Talents in University (No. NCET-08-0391)
文摘The concept and realization process of intelligent compaction for the construction of high roller compacted concrete dam were presented, as well as the theory of monitoring and intelligent feedback control. Based on the real-time analysis of the compaction index, a multiple regression model of the dam compactness was established and a realime estimation method of compaction quality for the entire work area of roller compacted concrete dam was proposed finally. The adaptive adjustment of the roiling process parameters was achieved, with the speed, the exciting force, the roller pass and the compaction thickness meeting the standards during the whole construction process. As a result, the compaction quality and construction efficiency can be improved. The research provides a new way for the construction quality control of roller compacted concrete dam.
