The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl pho...The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl phosphate(TBP), di(2-ethylhexyl) phosphoric acid(D2EHPA) and TBP + D2EHPA dissolved in 1-octanol were investigated, respectively. The influences of the initial concentrations of TBP, D2EHPA and TBP + D2EHPA on distribution ratio(D) were discussed, as well as the reactive extraction mechanism were proposed. The obvious intensification effect was observed when the mixture of TBP and D2EHPA was used as extractant. The best extraction conditions were found to be of the molar ratio of D2EHPA and TBP at 2:1 and the equilibrium aqueous pH at 3.50-4.50. D values increased with the increase of the total concentration of TBP and D2EHPA in 1-octanol. Especially, the analysis on the extraction mechanisms clearly indicate(i) TBP in 1-octanol shows negligible reactive extraction toward 4-HP,(ii) D2EHPA in 1-octanol exhibits moderate extraction effect by forming 4-HP:D2EHPA(1:1) and 4-HP:2D2EHPA(1:2) type complexes, while(iii) D2EHPA in TBP/1-octanol demonstrates the maximum distribution ratio with the 4-HP:D2EHPA(1:1) type complex domination. The discussion provides new insights on the mechanism and opens a new way for the intensified extraction of amphoteric organic compounds by using the mixture of multiple extractants in the diluent.展开更多
As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive ima...As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive image intensifier has been developed and demonstrated to achieve good spatial resolution and timing resolution.However,the influence of the working voltage on the performance of the neutron-sensitive imaging intensifier has not been studied.To optimize the performance of the neutron-sensitive image intensifier at different voltages,experiments have been performed at the China Spallation Neutron Source(CSNS)neutron beamline.The change in the light yield and imaging quality with different voltages has been acquired.It is shown that the image quality benefits from the high gain of the microchannel plate(MCP)and the high accelerating electric field between the MCP and the screen.Increasing the accelerating electric field is more effective than increasing the gain of MCPs for the improvement of the imaging quality.Increasing the total gain of the MCP stack can be realized more effectively by improving the gain of the standard MCP than that of the n MCP.These results offer a development direction for image intensifiers in the future.展开更多
AIM:To investigate whether neoadjuvant-intensified radiochemotherapy improved overall and disease-free survival in patients with locally advanced rectal cancer.METHODS:Between January 2007 and December 2011,80 patient...AIM:To investigate whether neoadjuvant-intensified radiochemotherapy improved overall and disease-free survival in patients with locally advanced rectal cancer.METHODS:Between January 2007 and December 2011,80 patients with histologically confirmed rectal adenocarcinoma were enrolled.Tumors were clinically classified as either T3 or T4 and by the N stage based on the presence or absence of positive regional lymph nodes.Patients received intensified combined modality treatment,consisting of neoadjuvant radiation therapy(50.4-54.0 Gy) and infusional chemotherapy(oxaliplatin 50 mg/m 2) on the first day of each week,plus five daily continuous infusions of fluorouracil(200 mg/m 2 per die) from the first day of radiation therapy until radiotherapy completion.Patients received five or six cycles of oxaliplatin based on performance status,clinical lymph node involvement,and potential risk of a non-sphincter-conserving surgical procedure.Surgery was planned 7 to 9 wk after the end of radiochemotherapy treatment;adjuvant chemotherapy treatment was left to the oncologist's discretion and was recommended in patients with positive lymph nodes.After treatment,all patients were monitored every three months for the first year and every six months for the subsequent years.RESULTS:Of the 80 patients enrolled,75 patients completed the programmed neoadjuvant radiochemotherapy treatment.All patients received the radiotherapy prescribed total dose;five patients suspended chemotherapy indefinitely because of chemotherapyrelated toxicity.At least five cycles of oxaliplatin were administered to 73 patients.Treatment was well tolerated with high compliance and a good level of toxicity.Most of the acute toxic effects observed were classified as grades 1-2.Proctitis grade 2 was the most common symptom(63.75%) and the earliest manifestation of acute toxicity.Acute toxicity grades 3-4 was reported in 30% of patients and grade 3 or 4 diarrhoea reported in just three patients(3.75%).Seventy-seven patients underwent surgery;low anterior resection was performed in 52 patients,Miles' surgery in 11 patients and total mesorectal excision in nine patients.Fifty patients showed tumor downsizing ≥ 50% pathological downstaging in 88.00% of tumors.Out of 75 patients surviving surgery,67 patients(89.33%) had some form of downstaging after preoperative treatment.A pathological complete response was achieved in 23.75% of patients and a nearly pathologic complete response(stage ypT1ypN0) in six patients.An involvement of the radial margin was never present.During surgery,intra-abdominal metastases were found in only one patient(1.25%).Initially,45 patients required an abdominoperineal resection due to a tumor distal margin ≤ 5 cm from the anal verge.Of these patients,only seven of them underwent Miles' surgery and sphincter preservation was guaranteed in 84.50% of patients in this subgroup.Fourteen patients received postoperative chemotherapy.In the full analysis of enrolled cohort,eight of the 80 patients died,with seven deaths related to rectal cancer and one to unrelated causes.Local recurrences were observed in seven patients(8.75%) and distant metastases in 17 cases(21.25%).The fiveyear rate of overall survival rate was 90.91%.Using a median follow-up time of 28.5 mo,the cumulative incidence of local recurrences was 8.75%,and the overall survival and disease-free survival rates were 90.00% and 70.00%,respectively.CONCLUSION:The results of this study suggest oxaliplatin chemotherapy has a beneficial effect on overall survival,likely due to an increase in local tumor control.展开更多
Experiments were conducted to investigate the behavior of the sequential system of intensified zero-valent iron process(IZVI) and anaerobic filter and biological aerated filter(AF/BAF) reactors for advanced treatment ...Experiments were conducted to investigate the behavior of the sequential system of intensified zero-valent iron process(IZVI) and anaerobic filter and biological aerated filter(AF/BAF) reactors for advanced treatment of biologically pretreated coking wastewater. Particular attention was paid to the performance of the integrated system for the removal of chemical oxygen demand(COD), ammonia nitrogen(NH3-N) and total nitrogen(TN). The average removal efficiencies of COD, NH3-N and TN were 76.28%, 96.76% and 59.97%, with the average effluent mass concentrations of 56, 0.53 and 18.83 mg/L, respectively, reaching the first grade of the national discharge standard. Moreover, the results of gas chromatography/mass spectrum(GC/MS) and gel permeation chromatography(GPC) analysis demonstrated that the refractory organic compounds with high relative molecular mass were partly removed in IZVI process by the function of oxidation-reduction, flocculation and adsorption which could also enhance the biodegradability of the system effluent. The removal efficiencies of NH3-N and TN were achieved mainly in the subsequent AF/BAF reactors by nitrification and denitrification. Overall, the results obtained show that the application of IZVI in combination with AF/BAF is a promising technology for advanced treatment of biologically pretreated coking wastewater.展开更多
The removal of disinfection by-products formation potential(DBPFP) in artificially intensified biological activated carbon(IBAC) process which is developed on the basis of traditional ozone granular activated carbon w...The removal of disinfection by-products formation potential(DBPFP) in artificially intensified biological activated carbon(IBAC) process which is developed on the basis of traditional ozone granular activated carbon was evaluated. By IBAC removals of 31% and 68% for THMFP and HAAFP were obtained respectively. Under identical conditions, the removals of the same substances were 4% and 32% respectively only by the granular activated carbon(GAC) process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. A clear linear correlation(R 2=0.9562 and R 2=0.9007) between DOC HAAFP removal rate and Empty Bed Contact Time(EBCT) of IBAC process was observed, while that between THMFP removal rate and EBCT of GAC was R 2=0.9782. In addition certain linear correlations between THMFP, HAAFP and UV 254 (R 2=0.855 and R 2=0.7702) were found for the treated water. For IBAC process there are also more advantages such as long backwashing cycle time, low backwashing intensity and prolonging activated carbon lifetime and so on.展开更多
A new process for the hydrometallurgy of refractory gold concentrates was presented. The process comprises grinding leaching, intensified alkaline leaching (IAL), cyanidation and adsorption. In a stirring type pulveri...A new process for the hydrometallurgy of refractory gold concentrates was presented. The process comprises grinding leaching, intensified alkaline leaching (IAL), cyanidation and adsorption. In a stirring type pulverizing leaching tower mill, the concentrate is ground to <35.6 μm of 95.5 % while simultaneously leached by NaOH of 12 kg/t, then carried out intensified alkaline leaching for 48 h by NaOH of 108 kg/t in enhanced agitation tanks with the pulp concentration of 40% solids at the environmental temperature of 9.5 ~ 13.5 ℃ and the environmental pressure of 10 5 Pa. The oxidation rate of As is 94.9%, and 47.6% for S. The total consumption of NaOH is only 20% of that theoretically calculated under the conditions of full oxidation at the same oxidation rates of arsenic to arsenate and sulfur to sulfate. The gold leaching rate by NaCN in 24 h is increased from 9.2% before pretreatment to 94.2%. The consumption of NaCN is 7.5 kg/t, which is one times less than that before pretreatment. The extraction cost of gold is about 422 Yuan/t.展开更多
Work has been done with extending the useful imaging and detection range of CCD.This was accomplished through direct optical coupling and bonding of i-mage intensifiers to the CCD.It has been shown that the useful ran...Work has been done with extending the useful imaging and detection range of CCD.This was accomplished through direct optical coupling and bonding of i-mage intensifiers to the CCD.It has been shown that the useful range of a CCD may be extended two orders of magnitude using these techniques in coupling a microchannel plate image intensifier to the CCD array.All of these works were done with presently available CCD made by China.展开更多
The traditional telecommunications operator of China has entered into a substantive network construction stage of NGN and new VoIP service in 2006. As the increasing understanding and the consideration of cost to VoIP...The traditional telecommunications operator of China has entered into a substantive network construction stage of NGN and new VoIP service in 2006. As the increasing understanding and the consideration of cost to VoIP, VoIP has become more acceptable for CIO of large-scale enterprises. Small and medium-scale enterprises are sensitive to communication cost, but influenced by the maturity of VoIP technology and reduction of VoIP equipment price, the market is intensified. All these drive the VoIP equipment entering into the actual purchase stage and promote the stable growth of VoIP equipment scale.展开更多
A pore-array intensified tube-in-tube microchannel(PA-TMC),which is characterized by high throughput and low pressure drop,was developed as a gas–liquid contactor.The sulfite oxidation method was used to determine th...A pore-array intensified tube-in-tube microchannel(PA-TMC),which is characterized by high throughput and low pressure drop,was developed as a gas–liquid contactor.The sulfite oxidation method was used to determine the oxygen efficiency(φ)and volumetric mass transfer coefficient(k_(L)a)of PA-TMC,and the mass transfer amount per unit energy(ε)was calculated by using the pressure drop.The effects of structural and operating parameters were investigated systematically,and the twophase flow behavior was monitored by using a charge-coupled device imaging system.The results indicated that the gas absorption efficiency and mass transfer performance of the PA-TMC were improved with increasing pore number,flow rate,and number of helical coil turns and decreasing pore size,row number,annular size,annular length,and surface tension.Theφ,εand k La of PA-TMC could reach 31.3%,1.73×10^(-4) mol/J,and 7.0 s-1,respectively.The Sherwood number was correlated with the investigated parameters to guide the design of PA-TMC in gas absorption and mass transfer processes.展开更多
Baosteel always aims at becoming one of the most profitable enterprises in the world, enjoying international competence, benchmarking with the world advanced level,pursuing innovation sustainable development. Recent y...Baosteel always aims at becoming one of the most profitable enterprises in the world, enjoying international competence, benchmarking with the world advanced level,pursuing innovation sustainable development. Recent years, Baosteel Iron-making Department has caught the opportunity of increasing steel demand; conquering disadvantages such as changeable up-stream market, fuel and raw material’s tight supplies and lower quality, etc. In our department, Major technical problems have been overcome, blast furnace intensified smelting technology improved, the cost of molten iron under control, blast furnace long-life span control technology made breakthrough, and Baosteel’s ironmaking capacity improved further.展开更多
基金supported by the Science and Technology Research Project of Henan Province (192102310490 and 212102310505)。
文摘The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl phosphate(TBP), di(2-ethylhexyl) phosphoric acid(D2EHPA) and TBP + D2EHPA dissolved in 1-octanol were investigated, respectively. The influences of the initial concentrations of TBP, D2EHPA and TBP + D2EHPA on distribution ratio(D) were discussed, as well as the reactive extraction mechanism were proposed. The obvious intensification effect was observed when the mixture of TBP and D2EHPA was used as extractant. The best extraction conditions were found to be of the molar ratio of D2EHPA and TBP at 2:1 and the equilibrium aqueous pH at 3.50-4.50. D values increased with the increase of the total concentration of TBP and D2EHPA in 1-octanol. Especially, the analysis on the extraction mechanisms clearly indicate(i) TBP in 1-octanol shows negligible reactive extraction toward 4-HP,(ii) D2EHPA in 1-octanol exhibits moderate extraction effect by forming 4-HP:D2EHPA(1:1) and 4-HP:2D2EHPA(1:2) type complexes, while(iii) D2EHPA in TBP/1-octanol demonstrates the maximum distribution ratio with the 4-HP:D2EHPA(1:1) type complex domination. The discussion provides new insights on the mechanism and opens a new way for the intensified extraction of amphoteric organic compounds by using the mixture of multiple extractants in the diluent.
基金Project supported by the National Key R&D Program of China (Grant Nos.2023YFC2206502 and 2021YFA1600703)the National Natural Science Foundation of China (Grant Nos.12175254 and 12227810)the Guangdong–Hong Kong–Macao Joint Laboratory for Neutron Scattering Science and Technology。
文摘As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive image intensifier has been developed and demonstrated to achieve good spatial resolution and timing resolution.However,the influence of the working voltage on the performance of the neutron-sensitive imaging intensifier has not been studied.To optimize the performance of the neutron-sensitive image intensifier at different voltages,experiments have been performed at the China Spallation Neutron Source(CSNS)neutron beamline.The change in the light yield and imaging quality with different voltages has been acquired.It is shown that the image quality benefits from the high gain of the microchannel plate(MCP)and the high accelerating electric field between the MCP and the screen.Increasing the accelerating electric field is more effective than increasing the gain of MCPs for the improvement of the imaging quality.Increasing the total gain of the MCP stack can be realized more effectively by improving the gain of the standard MCP than that of the n MCP.These results offer a development direction for image intensifiers in the future.
文摘AIM:To investigate whether neoadjuvant-intensified radiochemotherapy improved overall and disease-free survival in patients with locally advanced rectal cancer.METHODS:Between January 2007 and December 2011,80 patients with histologically confirmed rectal adenocarcinoma were enrolled.Tumors were clinically classified as either T3 or T4 and by the N stage based on the presence or absence of positive regional lymph nodes.Patients received intensified combined modality treatment,consisting of neoadjuvant radiation therapy(50.4-54.0 Gy) and infusional chemotherapy(oxaliplatin 50 mg/m 2) on the first day of each week,plus five daily continuous infusions of fluorouracil(200 mg/m 2 per die) from the first day of radiation therapy until radiotherapy completion.Patients received five or six cycles of oxaliplatin based on performance status,clinical lymph node involvement,and potential risk of a non-sphincter-conserving surgical procedure.Surgery was planned 7 to 9 wk after the end of radiochemotherapy treatment;adjuvant chemotherapy treatment was left to the oncologist's discretion and was recommended in patients with positive lymph nodes.After treatment,all patients were monitored every three months for the first year and every six months for the subsequent years.RESULTS:Of the 80 patients enrolled,75 patients completed the programmed neoadjuvant radiochemotherapy treatment.All patients received the radiotherapy prescribed total dose;five patients suspended chemotherapy indefinitely because of chemotherapyrelated toxicity.At least five cycles of oxaliplatin were administered to 73 patients.Treatment was well tolerated with high compliance and a good level of toxicity.Most of the acute toxic effects observed were classified as grades 1-2.Proctitis grade 2 was the most common symptom(63.75%) and the earliest manifestation of acute toxicity.Acute toxicity grades 3-4 was reported in 30% of patients and grade 3 or 4 diarrhoea reported in just three patients(3.75%).Seventy-seven patients underwent surgery;low anterior resection was performed in 52 patients,Miles' surgery in 11 patients and total mesorectal excision in nine patients.Fifty patients showed tumor downsizing ≥ 50% pathological downstaging in 88.00% of tumors.Out of 75 patients surviving surgery,67 patients(89.33%) had some form of downstaging after preoperative treatment.A pathological complete response was achieved in 23.75% of patients and a nearly pathologic complete response(stage ypT1ypN0) in six patients.An involvement of the radial margin was never present.During surgery,intra-abdominal metastases were found in only one patient(1.25%).Initially,45 patients required an abdominoperineal resection due to a tumor distal margin ≤ 5 cm from the anal verge.Of these patients,only seven of them underwent Miles' surgery and sphincter preservation was guaranteed in 84.50% of patients in this subgroup.Fourteen patients received postoperative chemotherapy.In the full analysis of enrolled cohort,eight of the 80 patients died,with seven deaths related to rectal cancer and one to unrelated causes.Local recurrences were observed in seven patients(8.75%) and distant metastases in 17 cases(21.25%).The fiveyear rate of overall survival rate was 90.91%.Using a median follow-up time of 28.5 mo,the cumulative incidence of local recurrences was 8.75%,and the overall survival and disease-free survival rates were 90.00% and 70.00%,respectively.CONCLUSION:The results of this study suggest oxaliplatin chemotherapy has a beneficial effect on overall survival,likely due to an increase in local tumor control.
基金Project(2006BAJ04A)suppprted by the National Sci-Tech Support Plan,China
文摘Experiments were conducted to investigate the behavior of the sequential system of intensified zero-valent iron process(IZVI) and anaerobic filter and biological aerated filter(AF/BAF) reactors for advanced treatment of biologically pretreated coking wastewater. Particular attention was paid to the performance of the integrated system for the removal of chemical oxygen demand(COD), ammonia nitrogen(NH3-N) and total nitrogen(TN). The average removal efficiencies of COD, NH3-N and TN were 76.28%, 96.76% and 59.97%, with the average effluent mass concentrations of 56, 0.53 and 18.83 mg/L, respectively, reaching the first grade of the national discharge standard. Moreover, the results of gas chromatography/mass spectrum(GC/MS) and gel permeation chromatography(GPC) analysis demonstrated that the refractory organic compounds with high relative molecular mass were partly removed in IZVI process by the function of oxidation-reduction, flocculation and adsorption which could also enhance the biodegradability of the system effluent. The removal efficiencies of NH3-N and TN were achieved mainly in the subsequent AF/BAF reactors by nitrification and denitrification. Overall, the results obtained show that the application of IZVI in combination with AF/BAF is a promising technology for advanced treatment of biologically pretreated coking wastewater.
文摘The removal of disinfection by-products formation potential(DBPFP) in artificially intensified biological activated carbon(IBAC) process which is developed on the basis of traditional ozone granular activated carbon was evaluated. By IBAC removals of 31% and 68% for THMFP and HAAFP were obtained respectively. Under identical conditions, the removals of the same substances were 4% and 32% respectively only by the granular activated carbon(GAC) process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. A clear linear correlation(R 2=0.9562 and R 2=0.9007) between DOC HAAFP removal rate and Empty Bed Contact Time(EBCT) of IBAC process was observed, while that between THMFP removal rate and EBCT of GAC was R 2=0.9782. In addition certain linear correlations between THMFP, HAAFP and UV 254 (R 2=0.855 and R 2=0.7702) were found for the treated water. For IBAC process there are also more advantages such as long backwashing cycle time, low backwashing intensity and prolonging activated carbon lifetime and so on.
文摘A new process for the hydrometallurgy of refractory gold concentrates was presented. The process comprises grinding leaching, intensified alkaline leaching (IAL), cyanidation and adsorption. In a stirring type pulverizing leaching tower mill, the concentrate is ground to <35.6 μm of 95.5 % while simultaneously leached by NaOH of 12 kg/t, then carried out intensified alkaline leaching for 48 h by NaOH of 108 kg/t in enhanced agitation tanks with the pulp concentration of 40% solids at the environmental temperature of 9.5 ~ 13.5 ℃ and the environmental pressure of 10 5 Pa. The oxidation rate of As is 94.9%, and 47.6% for S. The total consumption of NaOH is only 20% of that theoretically calculated under the conditions of full oxidation at the same oxidation rates of arsenic to arsenate and sulfur to sulfate. The gold leaching rate by NaCN in 24 h is increased from 9.2% before pretreatment to 94.2%. The consumption of NaCN is 7.5 kg/t, which is one times less than that before pretreatment. The extraction cost of gold is about 422 Yuan/t.
文摘Work has been done with extending the useful imaging and detection range of CCD.This was accomplished through direct optical coupling and bonding of i-mage intensifiers to the CCD.It has been shown that the useful range of a CCD may be extended two orders of magnitude using these techniques in coupling a microchannel plate image intensifier to the CCD array.All of these works were done with presently available CCD made by China.
文摘The traditional telecommunications operator of China has entered into a substantive network construction stage of NGN and new VoIP service in 2006. As the increasing understanding and the consideration of cost to VoIP, VoIP has become more acceptable for CIO of large-scale enterprises. Small and medium-scale enterprises are sensitive to communication cost, but influenced by the maturity of VoIP technology and reduction of VoIP equipment price, the market is intensified. All these drive the VoIP equipment entering into the actual purchase stage and promote the stable growth of VoIP equipment scale.
基金supported by National Key Research and Development Program(No.2016YFD0501402-04)National Natural Science Foundation of China(Nos.21776179,21621004)the Program for Changjiang Scholars and Innovative Research Team in University(No.IRT_15R46)。
文摘A pore-array intensified tube-in-tube microchannel(PA-TMC),which is characterized by high throughput and low pressure drop,was developed as a gas–liquid contactor.The sulfite oxidation method was used to determine the oxygen efficiency(φ)and volumetric mass transfer coefficient(k_(L)a)of PA-TMC,and the mass transfer amount per unit energy(ε)was calculated by using the pressure drop.The effects of structural and operating parameters were investigated systematically,and the twophase flow behavior was monitored by using a charge-coupled device imaging system.The results indicated that the gas absorption efficiency and mass transfer performance of the PA-TMC were improved with increasing pore number,flow rate,and number of helical coil turns and decreasing pore size,row number,annular size,annular length,and surface tension.Theφ,εand k La of PA-TMC could reach 31.3%,1.73×10^(-4) mol/J,and 7.0 s-1,respectively.The Sherwood number was correlated with the investigated parameters to guide the design of PA-TMC in gas absorption and mass transfer processes.
文摘Baosteel always aims at becoming one of the most profitable enterprises in the world, enjoying international competence, benchmarking with the world advanced level,pursuing innovation sustainable development. Recent years, Baosteel Iron-making Department has caught the opportunity of increasing steel demand; conquering disadvantages such as changeable up-stream market, fuel and raw material’s tight supplies and lower quality, etc. In our department, Major technical problems have been overcome, blast furnace intensified smelting technology improved, the cost of molten iron under control, blast furnace long-life span control technology made breakthrough, and Baosteel’s ironmaking capacity improved further.