On the conditions of different ethanol concentration, acids and catalyzers, the effects of ethanol pulping on the cellulose length of bamboo were studied. The results indicates that ethanol pulping has remarkable effe...On the conditions of different ethanol concentration, acids and catalyzers, the effects of ethanol pulping on the cellulose length of bamboo were studied. The results indicates that ethanol pulping has remarkable effects on the length of cellulose, which is clearly reduced with adding ethanol and acid. The margin of length of cellulose become smaller with the increase of the catalyzer. When the ethanol concentration was 70%, the concentration of acid was 0.3% and some NaOH was used as catalyzer, the length of cellulose was the longest.展开更多
To the Editor：Endoscopic retrograde cholangiopancreatography （ERCP） plays a vital role in the management ofpancreaticobiliary diseases in recent years and it concomitantly carries a risk of complications including ...To the Editor：Endoscopic retrograde cholangiopancreatography （ERCP） plays a vital role in the management ofpancreaticobiliary diseases in recent years and it concomitantly carries a risk of complications including post-ERCP pancreatitis,cholangitis,bleeding,and perforation.The incidence of primary post-ERCP complications ranges from 5.4% to 23.0%,and ERCP-induced perforation can occur in 0.3-1.0% of cases,but the associated mortality is high ranging from 8% to 23%.[1] Because of the confluence of the bile duct and pancreatic duct meet at the papilla in proximity to the site of perforation in the duodenum,there is a potential risk of leakage of bile and pancreatic juice into the retroperitoneal space or peritoneum.Patients with Stapfer＇s Type Ⅱ perforation （perivaterian perforation） generally suffered from systemic inflammatory response syndrome,which could progress rapidly to acute lung injury and acute renal insufficiency and even multiple organ failure.All of these contribute to the significantly high mortality.A timely recognition and appropriate treatment are crucial to the management of ERCP-induced perforation to reduce the overall mortality.Conventionally,surgery remains the primary treatment for iatrogenic perforations.With the improvement in endoscopic technique and development of new accessories,nonsurgical management with endoscopic treatment of perforation is increasingly being reported.[2] We report a retrospective analysis of ERCP-induced Stapfer＇s Type Ⅱ perforations over a 5-year period managed with nonsurgical approach combined with salvage ERCP.展开更多
Chemical components are the main factors affecting the mechanical properties of wood fibers. Lignin is one of the main components of wood cell walls and has a critical effect on the mechanical properties of paper pulp...Chemical components are the main factors affecting the mechanical properties of wood fibers. Lignin is one of the main components of wood cell walls and has a critical effect on the mechanical properties of paper pulp and wood fiber based composites. In this study, we carried out tensile tests on single mature latewood tracheids of Chi- nese fir （Cunninghamia lanciolata （Lamb.） Hook.）, using three different delignified treatment methods to obtain different amounts of lignin. We applied single fiber tests to study the effect of the amount of lignin on mechanical tensile proper- ties of single wood fibers at the cellular level. The results show that in their dry state, the modulus of elasticity of single fi- bers decreased with the reduction in the amount of Iignin; even their absolute values were not high. The amount of lignin affects the tensile strength and elongation of single fibers considerably. Tensile strength and elongation of single fibers increase with a reduction in the amount of lignin.展开更多
基金The National High-Tech Development863 Program of China (No.2002AA322050)
文摘On the conditions of different ethanol concentration, acids and catalyzers, the effects of ethanol pulping on the cellulose length of bamboo were studied. The results indicates that ethanol pulping has remarkable effects on the length of cellulose, which is clearly reduced with adding ethanol and acid. The margin of length of cellulose become smaller with the increase of the catalyzer. When the ethanol concentration was 70%, the concentration of acid was 0.3% and some NaOH was used as catalyzer, the length of cellulose was the longest.
基金This study was supported by grants from the National Natural Science Fund of China （No. 31570509）, CAS ＂Light of West China＂ Program （No. 90, 2015）, and Gansu Province Science Foundation for Youths （No. 17JR5RA259）.
文摘To the Editor：Endoscopic retrograde cholangiopancreatography （ERCP） plays a vital role in the management ofpancreaticobiliary diseases in recent years and it concomitantly carries a risk of complications including post-ERCP pancreatitis,cholangitis,bleeding,and perforation.The incidence of primary post-ERCP complications ranges from 5.4% to 23.0%,and ERCP-induced perforation can occur in 0.3-1.0% of cases,but the associated mortality is high ranging from 8% to 23%.[1] Because of the confluence of the bile duct and pancreatic duct meet at the papilla in proximity to the site of perforation in the duodenum,there is a potential risk of leakage of bile and pancreatic juice into the retroperitoneal space or peritoneum.Patients with Stapfer＇s Type Ⅱ perforation （perivaterian perforation） generally suffered from systemic inflammatory response syndrome,which could progress rapidly to acute lung injury and acute renal insufficiency and even multiple organ failure.All of these contribute to the significantly high mortality.A timely recognition and appropriate treatment are crucial to the management of ERCP-induced perforation to reduce the overall mortality.Conventionally,surgery remains the primary treatment for iatrogenic perforations.With the improvement in endoscopic technique and development of new accessories,nonsurgical management with endoscopic treatment of perforation is increasingly being reported.[2] We report a retrospective analysis of ERCP-induced Stapfer＇s Type Ⅱ perforations over a 5-year period managed with nonsurgical approach combined with salvage ERCP.
基金supported by the Key Program of the National Natural Science Foundation of China (Grant No. 30730076)
文摘Chemical components are the main factors affecting the mechanical properties of wood fibers. Lignin is one of the main components of wood cell walls and has a critical effect on the mechanical properties of paper pulp and wood fiber based composites. In this study, we carried out tensile tests on single mature latewood tracheids of Chi- nese fir （Cunninghamia lanciolata （Lamb.） Hook.）, using three different delignified treatment methods to obtain different amounts of lignin. We applied single fiber tests to study the effect of the amount of lignin on mechanical tensile proper- ties of single wood fibers at the cellular level. The results show that in their dry state, the modulus of elasticity of single fi- bers decreased with the reduction in the amount of Iignin; even their absolute values were not high. The amount of lignin affects the tensile strength and elongation of single fibers considerably. Tensile strength and elongation of single fibers increase with a reduction in the amount of lignin.
