Circulating CD133+ stem cells from the peripheral blood have been shown to be able to differentiate into numerous cell lineages. However, adults have only a small number of these circulating stem cells. The aim of the...Circulating CD133+ stem cells from the peripheral blood have been shown to be able to differentiate into numerous cell lineages. However, adults have only a small number of these circulating stem cells. The aim of the present study was to assess a new isolation and enrichment technique for CD133+ stem cells from peripheral blood with the use of Percoll density gradients. Our results demonstrated the presence of two large mononuclear bands when whole blood was centrifuged with 48% and 50% Percoll concentrations. Flow cytometric analysis (FACS) revealed a major CD133+ enrichment at the 48% Percoll concentration in one of the two bands. Further culture of these cells resulted in the formation of multiple colony-forming units. Our results suggest an advantage from using a simple Percoll gradient for successful CD133+ cell recovery, which could aid in differentiation and transplantation protocols.展开更多
Recovery of Ni-Cd batteries was studied by a self-designed vacuum-aided recovering system under laboratory conditions. The fundamental research on a process of disassembling and recovering selected materials from Ni-C...Recovery of Ni-Cd batteries was studied by a self-designed vacuum-aided recovering system under laboratory conditions. The fundamental research on a process of disassembling and recovering selected materials from Ni-Cd batterieswas conducted. The impacts of temperature, pressure and time were studied respectively. The mechanism of vacuum thermal recovering was also discussed. The results show that: Ni-Cd batteries can be recovered effectively byvacuum-aided recovering system at 573~1173 K. At constant pressure, the increase of temperature can improve theseparating efficiency of cadmium. When the temperature is 1173 K, the cadmium can evaporate completely fromthe residue during 3 h at 10 Pa. The reduction of pressure in the certain range is effective to separate cadmium byvacuum distillation. Distillation time is a very important factor affecting separation of cadmium.展开更多
以湖南株洲污染土壤作为研究对象,研究了Na-EDTA、NH_4-EDTA、Ca-EDTA在不同浓度下对土壤中Cd的去除效果,确定出适合的浓度与淋洗剂;并采用氯型717阴离子交换树脂对土壤淋洗液中的EDTA-Cd络合物进行吸附与回收试验,主要方法流程如下:采...以湖南株洲污染土壤作为研究对象,研究了Na-EDTA、NH_4-EDTA、Ca-EDTA在不同浓度下对土壤中Cd的去除效果,确定出适合的浓度与淋洗剂;并采用氯型717阴离子交换树脂对土壤淋洗液中的EDTA-Cd络合物进行吸附与回收试验,主要方法流程如下:采用静态法考察了固液比、pH值、时间、温度对树脂吸附EDTA-Cd络合物的影响,确定最佳吸附条件;采用上柱吸附法研究了在不同流速下穿透曲线的变化,确定树脂的穿透点;选取Fe_2(SO_4)_3多价金属盐溶液作为再生剂,对树脂中的EDTA-Cd络合物进行动态洗脱回收,测定出洗脱曲线与体积.随后进行连续5次吸附洗脱试验,探究树脂的再生性与树脂中EDTA-Cd络合物的回收效果.结果表明,在浓度为2.5 mmol·L^(-1)时,Na-EDTA、NH_4-EDTA、Ca-EDTA溶液对土壤中的Cd具有较好的去除效果,其去除率分别为64.75%、66.11%、68.29%.另外,在静态吸附过程中,随着固液比增加,树脂对EDTACd的吸附效率减少,在pH值为5.6时,对EDTA-Cd络合物吸附效率达到93.53%,树脂达到吸附平衡所需的时间为30—45 min,最佳反应温度区间为25—35℃;在动态吸附回收过程中,当上柱流速为4 m L·min^(-1)时,树脂达穿透点所需EDTA-Cd络合溶液为650 m L;再生剂Fe_2(SO_4)_3的洗脱体积为60 m L,洗脱溶液与吸附EDTA-Cd络合物溶液的体积比例达到1∶10.经过连续5次吸附洗脱试验后,树脂对EDTA-Cd络合物的去除率和再生率分别达到76.64%—93.43%、75.65%—84.19%.利用氯型717阴离子交换树脂提取以及回收土壤淋洗液中EDTA-Cd络合物是可行的.展开更多
文摘Circulating CD133+ stem cells from the peripheral blood have been shown to be able to differentiate into numerous cell lineages. However, adults have only a small number of these circulating stem cells. The aim of the present study was to assess a new isolation and enrichment technique for CD133+ stem cells from peripheral blood with the use of Percoll density gradients. Our results demonstrated the presence of two large mononuclear bands when whole blood was centrifuged with 48% and 50% Percoll concentrations. Flow cytometric analysis (FACS) revealed a major CD133+ enrichment at the 48% Percoll concentration in one of the two bands. Further culture of these cells resulted in the formation of multiple colony-forming units. Our results suggest an advantage from using a simple Percoll gradient for successful CD133+ cell recovery, which could aid in differentiation and transplantation protocols.
文摘Recovery of Ni-Cd batteries was studied by a self-designed vacuum-aided recovering system under laboratory conditions. The fundamental research on a process of disassembling and recovering selected materials from Ni-Cd batterieswas conducted. The impacts of temperature, pressure and time were studied respectively. The mechanism of vacuum thermal recovering was also discussed. The results show that: Ni-Cd batteries can be recovered effectively byvacuum-aided recovering system at 573~1173 K. At constant pressure, the increase of temperature can improve theseparating efficiency of cadmium. When the temperature is 1173 K, the cadmium can evaporate completely fromthe residue during 3 h at 10 Pa. The reduction of pressure in the certain range is effective to separate cadmium byvacuum distillation. Distillation time is a very important factor affecting separation of cadmium.
文摘以湖南株洲污染土壤作为研究对象,研究了Na-EDTA、NH_4-EDTA、Ca-EDTA在不同浓度下对土壤中Cd的去除效果,确定出适合的浓度与淋洗剂;并采用氯型717阴离子交换树脂对土壤淋洗液中的EDTA-Cd络合物进行吸附与回收试验,主要方法流程如下:采用静态法考察了固液比、pH值、时间、温度对树脂吸附EDTA-Cd络合物的影响,确定最佳吸附条件;采用上柱吸附法研究了在不同流速下穿透曲线的变化,确定树脂的穿透点;选取Fe_2(SO_4)_3多价金属盐溶液作为再生剂,对树脂中的EDTA-Cd络合物进行动态洗脱回收,测定出洗脱曲线与体积.随后进行连续5次吸附洗脱试验,探究树脂的再生性与树脂中EDTA-Cd络合物的回收效果.结果表明,在浓度为2.5 mmol·L^(-1)时,Na-EDTA、NH_4-EDTA、Ca-EDTA溶液对土壤中的Cd具有较好的去除效果,其去除率分别为64.75%、66.11%、68.29%.另外,在静态吸附过程中,随着固液比增加,树脂对EDTACd的吸附效率减少,在pH值为5.6时,对EDTA-Cd络合物吸附效率达到93.53%,树脂达到吸附平衡所需的时间为30—45 min,最佳反应温度区间为25—35℃;在动态吸附回收过程中,当上柱流速为4 m L·min^(-1)时,树脂达穿透点所需EDTA-Cd络合溶液为650 m L;再生剂Fe_2(SO_4)_3的洗脱体积为60 m L,洗脱溶液与吸附EDTA-Cd络合物溶液的体积比例达到1∶10.经过连续5次吸附洗脱试验后,树脂对EDTA-Cd络合物的去除率和再生率分别达到76.64%—93.43%、75.65%—84.19%.利用氯型717阴离子交换树脂提取以及回收土壤淋洗液中EDTA-Cd络合物是可行的.
