Preparation of superfine magnesium hydroxide with the bittern and ammonia was studied. The properties of the products were analyzed by laser granularity, X-ray diffraction, scanning electron microscope, the limiting o...Preparation of superfine magnesium hydroxide with the bittern and ammonia was studied. The properties of the products were analyzed by laser granularity, X-ray diffraction, scanning electron microscope, the limiting oxygen index and the wetting angle measurements. The results show that the mean particle size of the magnesium hydroxide is about 230 nm with a platelet shape and the specific surface area is about 48 m2/g when the temperature is 55 ℃ , and the ammonia and bittern are instilled simultaneously during the reaction process. After the modification, the limiting oxygen index and physical chemistry performance of the magnesium hydroxide were examined. The results show that the contact angle of magnesium hydroxide is 132.5? and the limiting oxygen index is 31.5 %, indicating that the modified magnesium hydroxide is an effective flame retardant and can be applied as flame retardant additives of the macromolecule compounds such as plastic, synthetic rubber and synthetic fibre.展开更多
BACKGROUND：High-volume hemofiltration （HVHF） is technically possible in severe acute pancreatitis （SAP） patients complicated with multiple organ dysfunction syndrome （MODS）. Continuous HVHF is expected to becom...BACKGROUND：High-volume hemofiltration （HVHF） is technically possible in severe acute pancreatitis （SAP） patients complicated with multiple organ dysfunction syndrome （MODS）. Continuous HVHF is expected to become a beneficial adjunct therapy for SAP complicated with MODS. In this study, we aimed to explore the effects of fluid resuscitation and HVHF on alveolar- arterial oxygen exchange, the Acute Physiology and Chronic Health Evaluation II （APACHE II） score in patients with refractory septic shock. METHODS：A total of 89 refractory septic shock patients, who were admitted to ICU, the Provincial Hospital affiliated to Shandong University from August 2006 to December 2009, were enrolled in this retrospective study. The patients were randomly divided into two groups： fluid resuscitation （group A, n=41）, and fluid resuscitation plus high-volume hemofiltration （group B, n=48）, The levels of O2 content of central venous blood （CcvO2）, arterial oxygen content （CaO2）, alveolar-arterial oxygen pressure difference P（A-a）DO2, ratio of arterial oxygen pressure/alveolar oxygen pressure （PaO2/ PAO2）, respiratory index （RI） and oxygenation index （OI） were determined. The oxygen exchange levels of the two groups were examined based on the arterial blood gas analysis at different times （0, 24, 72 hours and 7 days of treatment） in the two groups. The APACHE II score was calculated before and after 7-day treatment in the two groups. The levels of CcvO2, CaO2 on day 7 in group A were significantly lower than those in group B （CcvO2：0.60±0.24 vs, 0.72±0.28, P〈0.05; CaO2：0.84±0.43 vs. 0.94±0.46, P〈0.05）. The level of oxygen extraction rate （O2ER） in group A on the 7th day was significantly higher than that in group B （ 28.7±2.4 vs. 21.7±3.4, P〈0.01）. The levels of P（A-a）DO2 and RI in group B on the 7th day were significantly lower than those in group A. The levels of PaO2/PAO2 and OI in group B on 7th day were significantly higher than those in group A （P〈0.05 or P〈0.01）. The APACHE II score in the two groups reduced gradually after 7-day treatment, and the APACHE II score on the 7th day in group B was significantly lower than that in group A （8.2±3.8 vs. 17.2±6.8, P〈0.01）. HVHF combined with fluid resuscitation can improve alveolar- arterial-oxygen exchange, decrease the APACHE II score in patients with refractory septic shock, and thus it increases the survival rate of patients.展开更多
基金Project(2002-G-101) supported by the Key Program of Science and Technology of Qinghai Province, China
文摘Preparation of superfine magnesium hydroxide with the bittern and ammonia was studied. The properties of the products were analyzed by laser granularity, X-ray diffraction, scanning electron microscope, the limiting oxygen index and the wetting angle measurements. The results show that the mean particle size of the magnesium hydroxide is about 230 nm with a platelet shape and the specific surface area is about 48 m2/g when the temperature is 55 ℃ , and the ammonia and bittern are instilled simultaneously during the reaction process. After the modification, the limiting oxygen index and physical chemistry performance of the magnesium hydroxide were examined. The results show that the contact angle of magnesium hydroxide is 132.5? and the limiting oxygen index is 31.5 %, indicating that the modified magnesium hydroxide is an effective flame retardant and can be applied as flame retardant additives of the macromolecule compounds such as plastic, synthetic rubber and synthetic fibre.
基金This study was supported by a grant from the Natural Science Foundation of Shandong Province （Y2006C77）.
文摘BACKGROUND：High-volume hemofiltration （HVHF） is technically possible in severe acute pancreatitis （SAP） patients complicated with multiple organ dysfunction syndrome （MODS）. Continuous HVHF is expected to become a beneficial adjunct therapy for SAP complicated with MODS. In this study, we aimed to explore the effects of fluid resuscitation and HVHF on alveolar- arterial oxygen exchange, the Acute Physiology and Chronic Health Evaluation II （APACHE II） score in patients with refractory septic shock. METHODS：A total of 89 refractory septic shock patients, who were admitted to ICU, the Provincial Hospital affiliated to Shandong University from August 2006 to December 2009, were enrolled in this retrospective study. The patients were randomly divided into two groups： fluid resuscitation （group A, n=41）, and fluid resuscitation plus high-volume hemofiltration （group B, n=48）, The levels of O2 content of central venous blood （CcvO2）, arterial oxygen content （CaO2）, alveolar-arterial oxygen pressure difference P（A-a）DO2, ratio of arterial oxygen pressure/alveolar oxygen pressure （PaO2/ PAO2）, respiratory index （RI） and oxygenation index （OI） were determined. The oxygen exchange levels of the two groups were examined based on the arterial blood gas analysis at different times （0, 24, 72 hours and 7 days of treatment） in the two groups. The APACHE II score was calculated before and after 7-day treatment in the two groups. The levels of CcvO2, CaO2 on day 7 in group A were significantly lower than those in group B （CcvO2：0.60±0.24 vs, 0.72±0.28, P〈0.05; CaO2：0.84±0.43 vs. 0.94±0.46, P〈0.05）. The level of oxygen extraction rate （O2ER） in group A on the 7th day was significantly higher than that in group B （ 28.7±2.4 vs. 21.7±3.4, P〈0.01）. The levels of P（A-a）DO2 and RI in group B on the 7th day were significantly lower than those in group A. The levels of PaO2/PAO2 and OI in group B on 7th day were significantly higher than those in group A （P〈0.05 or P〈0.01）. The APACHE II score in the two groups reduced gradually after 7-day treatment, and the APACHE II score on the 7th day in group B was significantly lower than that in group A （8.2±3.8 vs. 17.2±6.8, P〈0.01）. HVHF combined with fluid resuscitation can improve alveolar- arterial-oxygen exchange, decrease the APACHE II score in patients with refractory septic shock, and thus it increases the survival rate of patients.
