Heat transfer coefficients in nucleate pool boiling were measured on a horizontal copper surface for refrigerants, HFC-134a, HFC-32, and HFC-125, their binary and ternary mixtures under saturated conditions at 0.9MPa....Heat transfer coefficients in nucleate pool boiling were measured on a horizontal copper surface for refrigerants, HFC-134a, HFC-32, and HFC-125, their binary and ternary mixtures under saturated conditions at 0.9MPa. Compared to pure components, both binary and ternary mixtures showed lower heat transfer coefficients.This deterioration was more pronounced as heat flux was increased. Experimental data were compared with some empirical and semi-empirical correlations available in literature. For binary mixture, the accuracy of the correlations varied considerably with mixtures and the heat flux. Experimental data for HFC-32/134a/125 were also compared with available correlated equation obtained by Thome. For ternary mixture, the boiling range of binary mixture composed by the pure fluids with the lowest and the medium boiling points, and their concentration difference had important effects on boiling heat transfer coefficients.展开更多
AIM: To investigate the therapeutic effect of somatostatin receptor type 2 (SSTR2) gene transfection on pancreatic carcinoma xenografts in vivo in experimental cancers. METHODS: Human pancreatic cancer cell line Panc-...AIM: To investigate the therapeutic effect of somatostatin receptor type 2 (SSTR2) gene transfection on pancreatic carcinoma xenografts in vivo in experimental cancers. METHODS: Human pancreatic cancer cell line Panc-1 was inoculated subcutaneously into the back of nude mice. When tumor nodules were grown as large as about 5 mmx5 mm days after inoculation, the mice were randomly divided into 3 groups (6 mice in each group). Group Ⅰ served as untreated control group. Group Ⅱ received an intratumoral injection of a combination of human cytomegalovirus promoter-6C (pCMV-6C) and lipofectamine 2000. Group Ⅲ received an intratumoral injection of a combination of pCMV-6C-SSTR2 and lipofectamine 2000. The rate of tumor growth was compared among these three groups. The expression of SSTR2 in these tumors was detected by immunohistochemistry and Western-blot. Apoptosis index (AI) in these tumors was examined by using TUNEL in situ. RESULTS: Intratumoral injection of a combination of pCMV-6C-SSTR2 and lipofectamine 2000 resulted in the expression of SSTR2 protein. The tumor size and weight in group Ⅲ (0.318±0.098 cm3, and 0.523±0.090 g, respectively) were significantly lower than those in group I (2.058±0.176 cms, and 1.412±0.146 g, respectively) and group Ⅱ (2.025±0.163 cm3, and 1.365±0.116 g, respectively) (P<0.05) The AI in group Ⅲ (1.47±0.13%) was significantly higher than that in groupⅠ(0.56±0.09%) and group Ⅱ (0.57±0.11%) (P<0.05). But there were no significant differences between groups Ⅰ and Ⅱ. CONCLUSION: Our data demonstrate that re-expression of SSTR2 gene has antitumor effects on experimental pancreatic cancer. Restoration of SSTR2 gene expression through gene transfer in vivo might be a potential gene therapy strategy for human pancreatic cancer.展开更多
Herein,we report a three-dimensional porous TiO_(2)/Fe_(2)TiO_(5)/Fe_(2)O_(3)(TFF)inverse opal through in situ thermal solid reactions for photoelectrochemical water splitting.The Fe_(2)TiO_(5) interfacial layer withi...Herein,we report a three-dimensional porous TiO_(2)/Fe_(2)TiO_(5)/Fe_(2)O_(3)(TFF)inverse opal through in situ thermal solid reactions for photoelectrochemical water splitting.The Fe_(2)TiO_(5) interfacial layer within TFF acting as a bridge to tightly connect to TiO_(2) and Fe_(2)O_(3) reduces the interfacial charge transfer resistance,and suppresses the bulk carrier recombination.The optimized TFF displays a remarkable photocurrent density of 0.54mAcm^(-2) at 1.23V vs.reversible hydrogen electrode(RHE),which is 25 times higher than that of TiO_(2)/Fe_(2)O_(3)(TF)inverse opal(0.02mAcm^(-2) at 1.23V vs.RHE).The charge transfer rate in TFF inverse opal is 2-8 times higher than that of TF in the potential range of 0.7-1.5V vs.RHE.The effects of the Fe_(2)TiO_(5) interfacial layer are further revealed by X-ray absorption spectroscopy and intensity-modulated photocurrent spectroscopy.This work offers an interfacial engineering protocol to improve charge separation and transfer for efficient solar water splitting.展开更多
基金Century Programme of Chinese Academy of Sciences.
文摘Heat transfer coefficients in nucleate pool boiling were measured on a horizontal copper surface for refrigerants, HFC-134a, HFC-32, and HFC-125, their binary and ternary mixtures under saturated conditions at 0.9MPa. Compared to pure components, both binary and ternary mixtures showed lower heat transfer coefficients.This deterioration was more pronounced as heat flux was increased. Experimental data were compared with some empirical and semi-empirical correlations available in literature. For binary mixture, the accuracy of the correlations varied considerably with mixtures and the heat flux. Experimental data for HFC-32/134a/125 were also compared with available correlated equation obtained by Thome. For ternary mixture, the boiling range of binary mixture composed by the pure fluids with the lowest and the medium boiling points, and their concentration difference had important effects on boiling heat transfer coefficients.
基金Supported by National Natural Science Foundation of China, No. 30271473
文摘AIM: To investigate the therapeutic effect of somatostatin receptor type 2 (SSTR2) gene transfection on pancreatic carcinoma xenografts in vivo in experimental cancers. METHODS: Human pancreatic cancer cell line Panc-1 was inoculated subcutaneously into the back of nude mice. When tumor nodules were grown as large as about 5 mmx5 mm days after inoculation, the mice were randomly divided into 3 groups (6 mice in each group). Group Ⅰ served as untreated control group. Group Ⅱ received an intratumoral injection of a combination of human cytomegalovirus promoter-6C (pCMV-6C) and lipofectamine 2000. Group Ⅲ received an intratumoral injection of a combination of pCMV-6C-SSTR2 and lipofectamine 2000. The rate of tumor growth was compared among these three groups. The expression of SSTR2 in these tumors was detected by immunohistochemistry and Western-blot. Apoptosis index (AI) in these tumors was examined by using TUNEL in situ. RESULTS: Intratumoral injection of a combination of pCMV-6C-SSTR2 and lipofectamine 2000 resulted in the expression of SSTR2 protein. The tumor size and weight in group Ⅲ (0.318±0.098 cm3, and 0.523±0.090 g, respectively) were significantly lower than those in group I (2.058±0.176 cms, and 1.412±0.146 g, respectively) and group Ⅱ (2.025±0.163 cm3, and 1.365±0.116 g, respectively) (P<0.05) The AI in group Ⅲ (1.47±0.13%) was significantly higher than that in groupⅠ(0.56±0.09%) and group Ⅱ (0.57±0.11%) (P<0.05). But there were no significant differences between groups Ⅰ and Ⅱ. CONCLUSION: Our data demonstrate that re-expression of SSTR2 gene has antitumor effects on experimental pancreatic cancer. Restoration of SSTR2 gene expression through gene transfer in vivo might be a potential gene therapy strategy for human pancreatic cancer.
基金supported by the National Natural Science Foundation of China(21771001 and 51872002)Anhui Provincial Natural Science Foundation(1708085ME120)+2 种基金the Program of Anhui Scientific and Technical Leaders Reserve Candidates(2018RH168)the Scholar Program for the Outstanding Innovative Talent of College Discipline(Specialty)the doctoral start-up fund and open fund for Discipline Construction,Institute of Physical Science and Information Technology,Anhui University.
文摘Herein,we report a three-dimensional porous TiO_(2)/Fe_(2)TiO_(5)/Fe_(2)O_(3)(TFF)inverse opal through in situ thermal solid reactions for photoelectrochemical water splitting.The Fe_(2)TiO_(5) interfacial layer within TFF acting as a bridge to tightly connect to TiO_(2) and Fe_(2)O_(3) reduces the interfacial charge transfer resistance,and suppresses the bulk carrier recombination.The optimized TFF displays a remarkable photocurrent density of 0.54mAcm^(-2) at 1.23V vs.reversible hydrogen electrode(RHE),which is 25 times higher than that of TiO_(2)/Fe_(2)O_(3)(TF)inverse opal(0.02mAcm^(-2) at 1.23V vs.RHE).The charge transfer rate in TFF inverse opal is 2-8 times higher than that of TF in the potential range of 0.7-1.5V vs.RHE.The effects of the Fe_(2)TiO_(5) interfacial layer are further revealed by X-ray absorption spectroscopy and intensity-modulated photocurrent spectroscopy.This work offers an interfacial engineering protocol to improve charge separation and transfer for efficient solar water splitting.
