The risks of metal compounds to human health are highlighted by the ubiquity of exposure and their persistence in the environment.Although compounds of As,Cd,Co,Cr,and Ni are known or“reasonably anticipated”to be ca...The risks of metal compounds to human health are highlighted by the ubiquity of exposure and their persistence in the environment.Although compounds of As,Cd,Co,Cr,and Ni are known or“reasonably anticipated”to be carcinogenic to humans and/or experimental animals, the cellular targets of these health hazards and the underlying mechanisms of their carcinogenic- ity are still unclear.We show in this report that dramatic,time-and dose-dependent cytoskeletal perturbations,especially in the distribution and organization patterns of microtubules and mi- crofilaments,two of the principal components of the cytoskeleton,occurred in 3T3 cells upon exposure to these metal salts.Each metal salt appeared to induce a different,typical pattern of cytoskeletal injury,probably reflecting the specificity of action of each metal ion.These results suggest that the cytoskeleton can indeed act as a target for injury by epigenetic carcinogenic metal compounds in the environment.These findings should help our efforts to understand the mechanisms of action of metal compounds at the subcellular and molecular levels.1989 Academic Press,Inc.展开更多
The authors have prepared suprameolecular systems of chiral Schiffbase ZnAZSB （Zn（II） complexes with azo-groups） or without ZnSB （azo-groups） and colloidal AuNP （gold nanoparticles） of 10, 40 and 80 nm diamete...The authors have prepared suprameolecular systems of chiral Schiffbase ZnAZSB （Zn（II） complexes with azo-groups） or without ZnSB （azo-groups） and colloidal AuNP （gold nanoparticles） of 10, 40 and 80 nm diameters. They exhibited gradual shifts of surface plasmon bands as well as fluorescence bands. The authors observed and discussed induced CD bands on gold nanoparticles from chiral ZnAZSB or ZnSB. Absence of cis-trans photoisomerization of ZnAZSB with AuNP also supported direct contact near the surface of AuNP. Quenching and splitting of fluorescence bands of ZnSB （λex = 550 nm and λem = 400 nm） depending on concentration of ZnSB and size of AuNP also suggested intermolecular （electric） interaction on the surface of AuNE Decrease of the intensity of the CD band around 380 nm resulted from reciprocal induced CD effect due to parallel arrangement of electric transition moments of ZnAZSB or ZnSB and surface of AuNP.展开更多
BACKGROUND： Stereo-tactic radiation therapy （SRT） is widely used to treat intracranial diseases, but some patients suffered from radiation induced brain edema after SRT. Once radiation induced brain edema occurs, t...BACKGROUND： Stereo-tactic radiation therapy （SRT） is widely used to treat intracranial diseases, but some patients suffered from radiation induced brain edema after SRT. Once radiation induced brain edema occurs, the treatment is quite difficult, and it always leads to a poor outcome. Dexamethasone has certain therapeutic effect on traumatic brain edema, but the biological mechanism is still unclear. OBJECTIVE ： To observe the effect of dexamethasone on the neutrophil expression of CD18.DESIGN ： A randomized control observation.SETTING： Changhai Hospital of the Second Military Medical University of Chinese PLA. MATERIALS ： The experiment was carried out in Changhai Hospital of the Second Military Medical University of Chinese PLA from January 1999 to December 1999. Twenty SD rats （male and female each in half） weighing （250±50） g were used. METHODS： Twenty SD rats were divided into four groups at random. ① Blank control group （n=5）： The rats were not treated without dexamethasone or irradiation;② Irradiation group （n=5）： The rats were given irradiation but no dexamethasone treatment; ③ Irradiation＋1 mg/kg dexamethasone group （n=5）; The rats were treated with irradiation and dexamethasone of 1 mg/kg; ④Irradiation＋5 mg/kg dexamethasone group （n=5）： The rats were treated with irradiation and dexamethasone of 5 mg/kg. The heads of the rats were irradiated with 10 MeV X-ray （30 Gy）, and brain tissue was removed after 2 weeks to observe the pathological changes. Blood samples were taken from the carotid artery, gradient centrifugation was used, and neutrophile layer was obtained, the level of neutrophile expression of CD18 mRNA and quantity of membrane proteins in blood were detected with Northern blot and flow cytometry respectively. MAIN OUTCOME MEASURES： ① Blood cell count; ② Pathological results; ③ level of neutrophile expression of CD18 mRNA and quantity of membrane proteins. RESULTS ： All the 20 SD rats were involved in the analysis of results without deletion. At 2 weeks after irradiation, obvious cell injury could be observed under light microscope. The level of neutrophile expression of CD18 mRNA and quantity of membrane proteins in blood were obviously increased, but the severity of cell injury was relieved in the irradiation＋1 and 5 mg/kg dexamethasone groups, and the CD18 expression was markedly suppressed （P 〈 0.05）, and the suppression was more obvious in the irradiation＋5 mg/kg dexamethasone group than in the irradiation＋1 mg/kg dexamethasone group （P 〈 0.01 ）. CONCLUSION： Dexamethasone can reduce the radiation induced brain edema by inhibiting the expression of CD18.展开更多
We report on the successful synthesis of cadmium sulfide （CdS） nanocages by laser ablation of bulk Cd target in thioacetamide （TAA） solution. The CdS nanocages exhibit obvious interior hollow spaces and distinctiv...We report on the successful synthesis of cadmium sulfide （CdS） nanocages by laser ablation of bulk Cd target in thioacetamide （TAA） solution. The CdS nanocages exhibit obvious interior hollow spaces and distinctive porous-shell structures. After laser ablation of Cd target in liquid condition, the unique structure should be attributed to the initial forma- tion of Cd micro-gas bubble via a model of micro-explosive boiling model. Surprisingly, the obtained CdS nanocages can provide a super-adsorption of methyl blue （MB） solution. The maximum adsorption capacity reaches up to 11813.3 mg/g, which is much higher than that reported in many previous researches. Without using any complicated stabilizers or soft directing agents, the pure CdS nanocages fabricated by laser ablation will serve as advanced absorbents in further research.展开更多
Objective To establish a stable and efficient method of culturing imDCs in vitro,and to explore the effect of GW5074,which blocks ERK1 /2 signal pathway in the process of immature dentritic cells ( imDCs) on inducing ...Objective To establish a stable and efficient method of culturing imDCs in vitro,and to explore the effect of GW5074,which blocks ERK1 /2 signal pathway in the process of immature dentritic cells ( imDCs) on inducing differentiation of the naive allogeneic CD4 + T展开更多
AIM: To explore the expression of reversion inducing cysteine-rich protein with Kazal motifs (RECK), vascular endothelial growth factor (VEGF) and endoglin (CD105) protein and its correlation with occurrence, developm...AIM: To explore the expression of reversion inducing cysteine-rich protein with Kazal motifs (RECK), vascular endothelial growth factor (VEGF) and endoglin (CD105) protein and its correlation with occurrence, development, invasion and metastasis in esophageal squamous cell carcinoma (ESCC). METHODS: Streptavidin-peroxidase (SP) immunohisto- chemistry was used to detect expression of RECK and VEGF in 62 cases of ESCC, 31 cases of adjacent atypical hyperplastic epithelium and 62 cases of normal esophageal epithelium. CD105 Mb was used to assess microvessel density (MVD). RESULTS: The expression of RECK was closely correlated with histological grade, infiltrative depth and lymphatic metastasis in ESCC (P < 0.05). The expression of RECK decreased during cancer development: normal esophageal epithelium (85.5%, 53/62), adjacent atypical hyperplastic epithelium (71.0%, 22/31), and carcinoma (59.7%, 37/62). There was a significant difference among the groups (P < 0.05). The expression of VEGF protein was closely correlated with infiltrative depth and lymphatic metastasis in ESCC (P < 0.05). The expression of VEGF protein increased during cancer development: normal esophageal epithelium (29.0%, 18/62), adjacent atypical hyperplastic epithelium (54.8%, 17/31), and carcinoma (67.7%, 42/62). There was a significant difference among the groups (P < 0.05). MVDCD105 increased in accordance with histological grade, butthere was no significant difference (grade Ⅰ, 36.92 ± 10.85; grade Ⅱ, 37.65 ± 9.50; and grade Ⅲ, 38.06 ± 12.19). The MVDCD105 was closely correlated with infiltration and lymphatic metastasis in ESCC (P < 0.05). The expression of RECK was inversely correlated with the expression of VEGF and CD105. CONCLUSION: RECK, VEGF and CD105 play important roles in the infiltration, metastasis and carcinogenesis in esophageal carcinoma. Angiogenesis in ESCC may be promoted by over-expression of CD105.展开更多
Summary： In order to investigate the expression of nerve growth factor （NGF） and hypoxia inducible factor-1α （HIF-1α） and its correlation with angiogenesis in non-small cell lung cancer （NSCLC）, paraffin-embe...Summary： In order to investigate the expression of nerve growth factor （NGF） and hypoxia inducible factor-1α （HIF-1α） and its correlation with angiogenesis in non-small cell lung cancer （NSCLC）, paraffin-embedded tissue blocks from 20 patients with NSCLC were examined. Twenty corresponding para-cancerous lung tissue specimens were obtained to serve as a control. The expression of NGF, HIF-1α, and vascular endothelial growth factor （VEGF） in the NSCLC tissues was detected by using immunohistochemistry. The microvascular density （MVD） was determined by CD31 staining. The resuits showed that the expression levels ofNGF, HIF-1α and VEGF in the NSCLC tissues were remarkably higher than those in the para-cancerous lung tissues （P〈0.05）. There was significant difference in the MVD between the NSCLC tissues （9.19±1.43） and para-cancerous lung tissues （2.23±1.19） （P〈0.05）. There were positive correlations between NGF and VEGF, between HIF-1α and VEGF, and between NGF and HIF-1α in NSCLC tissues, with the spearman correlation coefficient being 0.588, 0.519 and 0.588, respectively. In NSCLC tissues, the MVD had a positive correlation with the three factors （P〈0.05）. Theses results suggest that NGF and HIF-1α are synergically involved in the angiogenesis of NSCLC.展开更多
CD93 and GAIP-interacting protein, C termius （GIPC） have been shown to interactively alter phagocytic processes of immune cells. CD93 and GIPC expression and localization during cen-tral nervous system inflammation ...CD93 and GAIP-interacting protein, C termius （GIPC） have been shown to interactively alter phagocytic processes of immune cells. CD93 and GIPC expression and localization during cen-tral nervous system inflammation have not yet been reported. In this study, we established a rat model of brain inlfammation by lipopolysaccharide injection to the lateral ventricle. In the brain of rats with inlfammation, western blots showed increased CD93 expression that decreased over time. GIPC expression was unaltered. Immunohistochemistry demonstrated extensive distribution of CD93 expression mainly in cell membranes in the cerebral cortex. After lipopoly-saccharide stimulation, CD93 expression increased and then reduced, with distinct staining in the cytoplasm and nucleus. Double immunolfuorescence staining in cerebral cortex of normal rats showed that CD93 and GIPC widely expressed in resting microglia and neurons. CD93 was mainly expressed in microglial and neuronal cell membranes, while GIPC was expressed in both cell membrane and cytoplasm. In the cerebral cortex at 9 hours after model establishment, CD93-immunoreactive signal diminished in microglial membrane, with cytoplasmic transloca-tion and aggregation detected. GIPC localization was unaltered in neurons and microglia. These results are the ifrst to demonstrate CD93 participation in pathophysiological processes of central nervous system inlfammation.展开更多
Sphere-like mesoporous CdS nanocrystals with high crystallinity and big surface area were successfully fabricated by ultrasound irradiation at room temperature. The as-synthesized CdS with and without ultrasound irra ...Sphere-like mesoporous CdS nanocrystals with high crystallinity and big surface area were successfully fabricated by ultrasound irradiation at room temperature. The as-synthesized CdS with and without ultrasound irra diation was investigated by the characterizations of X-ray diffraction（XRD）, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, and Brunauer-Emmett-Teller（BET） surface areas. The photocatalytic acti vity of the CdS was evaluated by photocatalytic degradation of methyl orange under visible light（λ〉420 nm） irradia tion. A possible mechanism for the formation of the CdS nanocrystals with mesoporous structure under ultrasound irradiation was proposed. The results show that both the template role of the triblock copolymer of P123 and the effect of ultrasound-induced aggregation are mainly responsible for the formation of mesoporous structure. On the other hand, the energy generated from acoustic cavitation can effectively accelerate the crystallization process of the amorphous CdS.展开更多
Microbially induced calcite precipitation(MICP)technique utilizes ureolytic bacteria to decompose urea and generate carbonate ions for metal combination.MICP can remediate heavy metal(e.g.,Cd)contaminated soils while ...Microbially induced calcite precipitation(MICP)technique utilizes ureolytic bacteria to decompose urea and generate carbonate ions for metal combination.MICP can remediate heavy metal(e.g.,Cd)contaminated soils while maintaining or even improving soil functions,but its efficiency in agricultural soil practical application still needs to be enhanced.Here,we constructed a biochar-bacteria(2B)partnership in which biochar provides high nutrition and diverse sorption sites.Using the 2B system,Cd immobilization effectiveness and the underlying mechanism were examined along with the soil properties and soil functions.Results showed that compared to the single biochar and ureolytic bacteria systems,soil Cd mobility was reduced by 23.6%and 45.8%through co-precipitating with CaCO_(3) as otavite(CdCO_(3))in the 2B system,whereas soil fertility,bacterial diversity,and richness increased by 11.7-90.2%,5.4-16.1%,and 6.8-54.7%,respectively.Moreover,the abundances of Proteobacteria and Firmicutes were enhanced in the 2B system.Notably,Sporosarcina and Bacillus(Firmicutes genus)that carry the ureC gene were boosted in the system,further implicating the microbiological mechanism in reducing Cd migration and its bioavailability in soil.Overall,the constructed 2B system was efficient in soil Cd immobilization by strengthening the ureolytic bacteria growth and their nutrient supply in the bacteria-rich soil ecosystem.展开更多
文摘The risks of metal compounds to human health are highlighted by the ubiquity of exposure and their persistence in the environment.Although compounds of As,Cd,Co,Cr,and Ni are known or“reasonably anticipated”to be carcinogenic to humans and/or experimental animals, the cellular targets of these health hazards and the underlying mechanisms of their carcinogenic- ity are still unclear.We show in this report that dramatic,time-and dose-dependent cytoskeletal perturbations,especially in the distribution and organization patterns of microtubules and mi- crofilaments,two of the principal components of the cytoskeleton,occurred in 3T3 cells upon exposure to these metal salts.Each metal salt appeared to induce a different,typical pattern of cytoskeletal injury,probably reflecting the specificity of action of each metal ion.These results suggest that the cytoskeleton can indeed act as a target for injury by epigenetic carcinogenic metal compounds in the environment.These findings should help our efforts to understand the mechanisms of action of metal compounds at the subcellular and molecular levels.1989 Academic Press,Inc.
文摘The authors have prepared suprameolecular systems of chiral Schiffbase ZnAZSB （Zn（II） complexes with azo-groups） or without ZnSB （azo-groups） and colloidal AuNP （gold nanoparticles） of 10, 40 and 80 nm diameters. They exhibited gradual shifts of surface plasmon bands as well as fluorescence bands. The authors observed and discussed induced CD bands on gold nanoparticles from chiral ZnAZSB or ZnSB. Absence of cis-trans photoisomerization of ZnAZSB with AuNP also supported direct contact near the surface of AuNP. Quenching and splitting of fluorescence bands of ZnSB （λex = 550 nm and λem = 400 nm） depending on concentration of ZnSB and size of AuNP also suggested intermolecular （electric） interaction on the surface of AuNE Decrease of the intensity of the CD band around 380 nm resulted from reciprocal induced CD effect due to parallel arrangement of electric transition moments of ZnAZSB or ZnSB and surface of AuNP.
文摘BACKGROUND： Stereo-tactic radiation therapy （SRT） is widely used to treat intracranial diseases, but some patients suffered from radiation induced brain edema after SRT. Once radiation induced brain edema occurs, the treatment is quite difficult, and it always leads to a poor outcome. Dexamethasone has certain therapeutic effect on traumatic brain edema, but the biological mechanism is still unclear. OBJECTIVE ： To observe the effect of dexamethasone on the neutrophil expression of CD18.DESIGN ： A randomized control observation.SETTING： Changhai Hospital of the Second Military Medical University of Chinese PLA. MATERIALS ： The experiment was carried out in Changhai Hospital of the Second Military Medical University of Chinese PLA from January 1999 to December 1999. Twenty SD rats （male and female each in half） weighing （250±50） g were used. METHODS： Twenty SD rats were divided into four groups at random. ① Blank control group （n=5）： The rats were not treated without dexamethasone or irradiation;② Irradiation group （n=5）： The rats were given irradiation but no dexamethasone treatment; ③ Irradiation＋1 mg/kg dexamethasone group （n=5）; The rats were treated with irradiation and dexamethasone of 1 mg/kg; ④Irradiation＋5 mg/kg dexamethasone group （n=5）： The rats were treated with irradiation and dexamethasone of 5 mg/kg. The heads of the rats were irradiated with 10 MeV X-ray （30 Gy）, and brain tissue was removed after 2 weeks to observe the pathological changes. Blood samples were taken from the carotid artery, gradient centrifugation was used, and neutrophile layer was obtained, the level of neutrophile expression of CD18 mRNA and quantity of membrane proteins in blood were detected with Northern blot and flow cytometry respectively. MAIN OUTCOME MEASURES： ① Blood cell count; ② Pathological results; ③ level of neutrophile expression of CD18 mRNA and quantity of membrane proteins. RESULTS ： All the 20 SD rats were involved in the analysis of results without deletion. At 2 weeks after irradiation, obvious cell injury could be observed under light microscope. The level of neutrophile expression of CD18 mRNA and quantity of membrane proteins in blood were obviously increased, but the severity of cell injury was relieved in the irradiation＋1 and 5 mg/kg dexamethasone groups, and the CD18 expression was markedly suppressed （P 〈 0.05）, and the suppression was more obvious in the irradiation＋5 mg/kg dexamethasone group than in the irradiation＋1 mg/kg dexamethasone group （P 〈 0.01 ）. CONCLUSION： Dexamethasone can reduce the radiation induced brain edema by inhibiting the expression of CD18.
基金supported by the National Natural Science Foundation of China(Grant Nos.11575102 and 11105085)the Fundamental Research Funds of Shandong University,China(Grant No.2015JC007)
文摘We report on the successful synthesis of cadmium sulfide （CdS） nanocages by laser ablation of bulk Cd target in thioacetamide （TAA） solution. The CdS nanocages exhibit obvious interior hollow spaces and distinctive porous-shell structures. After laser ablation of Cd target in liquid condition, the unique structure should be attributed to the initial forma- tion of Cd micro-gas bubble via a model of micro-explosive boiling model. Surprisingly, the obtained CdS nanocages can provide a super-adsorption of methyl blue （MB） solution. The maximum adsorption capacity reaches up to 11813.3 mg/g, which is much higher than that reported in many previous researches. Without using any complicated stabilizers or soft directing agents, the pure CdS nanocages fabricated by laser ablation will serve as advanced absorbents in further research.
文摘Objective To establish a stable and efficient method of culturing imDCs in vitro,and to explore the effect of GW5074,which blocks ERK1 /2 signal pathway in the process of immature dentritic cells ( imDCs) on inducing differentiation of the naive allogeneic CD4 + T
基金Supported by The "Tenth Five-Year Plan" Research Foundation for the Key Constructional Project ("211 Project") of Zhengzhou University, He'nan Province, China
文摘AIM: To explore the expression of reversion inducing cysteine-rich protein with Kazal motifs (RECK), vascular endothelial growth factor (VEGF) and endoglin (CD105) protein and its correlation with occurrence, development, invasion and metastasis in esophageal squamous cell carcinoma (ESCC). METHODS: Streptavidin-peroxidase (SP) immunohisto- chemistry was used to detect expression of RECK and VEGF in 62 cases of ESCC, 31 cases of adjacent atypical hyperplastic epithelium and 62 cases of normal esophageal epithelium. CD105 Mb was used to assess microvessel density (MVD). RESULTS: The expression of RECK was closely correlated with histological grade, infiltrative depth and lymphatic metastasis in ESCC (P < 0.05). The expression of RECK decreased during cancer development: normal esophageal epithelium (85.5%, 53/62), adjacent atypical hyperplastic epithelium (71.0%, 22/31), and carcinoma (59.7%, 37/62). There was a significant difference among the groups (P < 0.05). The expression of VEGF protein was closely correlated with infiltrative depth and lymphatic metastasis in ESCC (P < 0.05). The expression of VEGF protein increased during cancer development: normal esophageal epithelium (29.0%, 18/62), adjacent atypical hyperplastic epithelium (54.8%, 17/31), and carcinoma (67.7%, 42/62). There was a significant difference among the groups (P < 0.05). MVDCD105 increased in accordance with histological grade, butthere was no significant difference (grade Ⅰ, 36.92 ± 10.85; grade Ⅱ, 37.65 ± 9.50; and grade Ⅲ, 38.06 ± 12.19). The MVDCD105 was closely correlated with infiltration and lymphatic metastasis in ESCC (P < 0.05). The expression of RECK was inversely correlated with the expression of VEGF and CD105. CONCLUSION: RECK, VEGF and CD105 play important roles in the infiltration, metastasis and carcinogenesis in esophageal carcinoma. Angiogenesis in ESCC may be promoted by over-expression of CD105.
基金supported by the Scientific Research Program of Health Department of Hubei Province,China(No.JX6B04)
文摘Summary： In order to investigate the expression of nerve growth factor （NGF） and hypoxia inducible factor-1α （HIF-1α） and its correlation with angiogenesis in non-small cell lung cancer （NSCLC）, paraffin-embedded tissue blocks from 20 patients with NSCLC were examined. Twenty corresponding para-cancerous lung tissue specimens were obtained to serve as a control. The expression of NGF, HIF-1α, and vascular endothelial growth factor （VEGF） in the NSCLC tissues was detected by using immunohistochemistry. The microvascular density （MVD） was determined by CD31 staining. The resuits showed that the expression levels ofNGF, HIF-1α and VEGF in the NSCLC tissues were remarkably higher than those in the para-cancerous lung tissues （P〈0.05）. There was significant difference in the MVD between the NSCLC tissues （9.19±1.43） and para-cancerous lung tissues （2.23±1.19） （P〈0.05）. There were positive correlations between NGF and VEGF, between HIF-1α and VEGF, and between NGF and HIF-1α in NSCLC tissues, with the spearman correlation coefficient being 0.588, 0.519 and 0.588, respectively. In NSCLC tissues, the MVD had a positive correlation with the three factors （P〈0.05）. Theses results suggest that NGF and HIF-1α are synergically involved in the angiogenesis of NSCLC.
基金supported by the National Natural Science Foundation of China,No.31170766the Nantong Municipal Social Undertakings Technological Innovation and Demonstration Project Foundation,No.HS2012032the Natural Science Pre-research Project Foundation of Nantong University in 2012,No.12ZY020
文摘CD93 and GAIP-interacting protein, C termius （GIPC） have been shown to interactively alter phagocytic processes of immune cells. CD93 and GIPC expression and localization during cen-tral nervous system inflammation have not yet been reported. In this study, we established a rat model of brain inlfammation by lipopolysaccharide injection to the lateral ventricle. In the brain of rats with inlfammation, western blots showed increased CD93 expression that decreased over time. GIPC expression was unaltered. Immunohistochemistry demonstrated extensive distribution of CD93 expression mainly in cell membranes in the cerebral cortex. After lipopoly-saccharide stimulation, CD93 expression increased and then reduced, with distinct staining in the cytoplasm and nucleus. Double immunolfuorescence staining in cerebral cortex of normal rats showed that CD93 and GIPC widely expressed in resting microglia and neurons. CD93 was mainly expressed in microglial and neuronal cell membranes, while GIPC was expressed in both cell membrane and cytoplasm. In the cerebral cortex at 9 hours after model establishment, CD93-immunoreactive signal diminished in microglial membrane, with cytoplasmic transloca-tion and aggregation detected. GIPC localization was unaltered in neurons and microglia. These results are the ifrst to demonstrate CD93 participation in pathophysiological processes of central nervous system inlfammation.
基金Supported by the National Natural Science Foundation of China(No.21067004)the Natural Science Foundation of Jiangxi Province, China(No.2010GZH0048)the Open Foundation of State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, China(No.200906)
文摘Sphere-like mesoporous CdS nanocrystals with high crystallinity and big surface area were successfully fabricated by ultrasound irradiation at room temperature. The as-synthesized CdS with and without ultrasound irra diation was investigated by the characterizations of X-ray diffraction（XRD）, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, and Brunauer-Emmett-Teller（BET） surface areas. The photocatalytic acti vity of the CdS was evaluated by photocatalytic degradation of methyl orange under visible light（λ〉420 nm） irradia tion. A possible mechanism for the formation of the CdS nanocrystals with mesoporous structure under ultrasound irradiation was proposed. The results show that both the template role of the triblock copolymer of P123 and the effect of ultrasound-induced aggregation are mainly responsible for the formation of mesoporous structure. On the other hand, the energy generated from acoustic cavitation can effectively accelerate the crystallization process of the amorphous CdS.
基金National Natural Science Foundation of China(Grant No.4210070784)Key Program of Chengdu Science and Technology Bureau(Grant Nos.2020-YF09-00023-SN and 2020-YF09-00012-SN).
文摘Microbially induced calcite precipitation(MICP)technique utilizes ureolytic bacteria to decompose urea and generate carbonate ions for metal combination.MICP can remediate heavy metal(e.g.,Cd)contaminated soils while maintaining or even improving soil functions,but its efficiency in agricultural soil practical application still needs to be enhanced.Here,we constructed a biochar-bacteria(2B)partnership in which biochar provides high nutrition and diverse sorption sites.Using the 2B system,Cd immobilization effectiveness and the underlying mechanism were examined along with the soil properties and soil functions.Results showed that compared to the single biochar and ureolytic bacteria systems,soil Cd mobility was reduced by 23.6%and 45.8%through co-precipitating with CaCO_(3) as otavite(CdCO_(3))in the 2B system,whereas soil fertility,bacterial diversity,and richness increased by 11.7-90.2%,5.4-16.1%,and 6.8-54.7%,respectively.Moreover,the abundances of Proteobacteria and Firmicutes were enhanced in the 2B system.Notably,Sporosarcina and Bacillus(Firmicutes genus)that carry the ureC gene were boosted in the system,further implicating the microbiological mechanism in reducing Cd migration and its bioavailability in soil.Overall,the constructed 2B system was efficient in soil Cd immobilization by strengthening the ureolytic bacteria growth and their nutrient supply in the bacteria-rich soil ecosystem.
