230Pa was produced through the 232Th(p,3n)230Pa reaction in the irradiated ThO2 powder targets with 35 MeV proton beam. Pa was radiochemically separated from ThO2 and other reaction products, and then thin sources of ...230Pa was produced through the 232Th(p,3n)230Pa reaction in the irradiated ThO2 powder targets with 35 MeV proton beam. Pa was radiochemically separated from ThO2 and other reaction products, and then thin sources of 230Paβ-230U were prepared. The polyethylene-terephthalate (lavsan) films were selected as solid track detector searching for the cluster activity of 230U. The gamma activity of 230Pa in the sources was measured using a HPGe detector. The lavsan films were etched in NaOH solution and the etched films were scanned under an optical microscope. The exotic nuclear decay of 230U by emission of 22Ne was observed. A branching ratio relative to α decay was deduced, B =λNe/λα= (1.3±0.8)×10-14 for 22Ne emission from 230U.展开更多
A new method of using dynamic equalization technology to realize the maximum energy storage uti-lization was presented to overcome the influence of the disaccord among units of series super capacitor(SC) bank and ensu...A new method of using dynamic equalization technology to realize the maximum energy storage uti-lization was presented to overcome the influence of the disaccord among units of series super capacitor(SC) bank and ensure that the units could work safely.By considering in combination with the high spe-cific power,low working voltage,wide voltage working range and nonlinear external characteristics,wepresent constant duty ratio pulse frequency modulation mode and fuzzy control method based on state pre-diction in the active equalization circuit and accomplish the software and hardware design for the equaliza-tion system.The simulation analysis and experiment results of constant current multi-cycle and variablecurrent multi-cycle charge-discharge process verify the validity of the design.展开更多
The conflict detection and resolution in collaborative design is a key issue to maintain multi disciplinary design consistency. This paper proposes a new method for conflict detection and resolution based on constrain...The conflict detection and resolution in collaborative design is a key issue to maintain multi disciplinary design consistency. This paper proposes a new method for conflict detection and resolution based on constraint satisfaction technique. The representation of design constraint, the interval arithmetic of the constraint satisfaction problem CSP and the conflict resolution strategy based on constraint relaxation and adjustment are introduced. A constraint satisfaction based conflict detection and resolution tool CSCDR is then developed. It can help collaborative designers to detect and resolve the conflicts in time in the early stage of the design process so that the unnecessary design iteration and repeated negotiation are avoided and the design efficiency is then much improved. A design case illustrates the effectiveness of CSCDR.展开更多
The Beijing Astronomical Observatory (BAO) 0.6 m telescope has been used for nearby supernova survey in more than 3000 fields, covering a total area of 235 deg2. More than 260000 CCD images have been collected since A...The Beijing Astronomical Observatory (BAO) 0.6 m telescope has been used for nearby supernova survey in more than 3000 fields, covering a total area of 235 deg2. More than 260000 CCD images have been collected since April 1996, with 45 supernovae discovered. We searched for variables in about 90000 images taken during 1996-1998. For the fields in which long period variables (LPVs) were discovered, we reduced further images taken from 1999 to 2000, for the period estimation. Among the 280000 stars selected from the survey fields, i.e., brighter than 18 mag, we discovered seven new LPVs and reconfirmed three known LPVs. Additionally, we found 146 variable star candidates, and reconfirmed about 20 previously known or suspected objects.展开更多
Dear Editor,In the late stages of the retroviral life cycle,the transcription of viral pre-m RNA is initiated at the 5′long terminal repeat(5′LTR)and terminated at the 3′LTR;the full-length and spliced viral RNAs a...Dear Editor,In the late stages of the retroviral life cycle,the transcription of viral pre-m RNA is initiated at the 5′long terminal repeat(5′LTR)and terminated at the 3′LTR;the full-length and spliced viral RNAs are transported out of the nucleus and serve as templates for the translation of viral proteins or alternatively as the full-length viral genome to be packaged into virus particles.展开更多
Objective: To observe the clinical effect of Yiqi Jianpi Bushen recipe (YQJPBS, 益气健脾补肾方) in antagonizing nephrotoxicity and hematological toxicity by cisplatin (CDDP). Methods: The patients with different types...Objective: To observe the clinical effect of Yiqi Jianpi Bushen recipe (YQJPBS, 益气健脾补肾方) in antagonizing nephrotoxicity and hematological toxicity by cisplatin (CDDP). Methods: The patients with different types of carcinomas were divided into two groups. One group was treated by western medicine (WM), i.e. cisplatin combined with diuretic therapy. The other group by Chinese medicine (CM). One day before chemotherapy, YQJPBS was given orally. Urinary enzyme (NAG, γ-GT, ALP) and serum erythropoietin (Epo) were used as the key monitoring indicator. Results: The early renal damage by CDDP remains near proximal convoluted tubule, which leads to the rising of urinary enzyme. So urinary enzyme of the CM group was obviously lower than that of the WM group. The lesion of renal interstitial cells that produce Epo did not cause the serum Epo of WM group to rise obviously 15 days later. As a result there was 40% patients whose RBC and Hb became lower than the standard count. While serum Epo of CM group was higher than that of WM group, only 5% patients in the CM group had their RBC and Hb lowered. Conclusion: YQJPBS can effectively antagonize nephrotoxicity and hematological toxicity induced by CDDP.展开更多
基金Supported by the National Natural Science Foundation of China (No. 10075063) Chinese Academy of Sciences (TK95T-03)
文摘230Pa was produced through the 232Th(p,3n)230Pa reaction in the irradiated ThO2 powder targets with 35 MeV proton beam. Pa was radiochemically separated from ThO2 and other reaction products, and then thin sources of 230Paβ-230U were prepared. The polyethylene-terephthalate (lavsan) films were selected as solid track detector searching for the cluster activity of 230U. The gamma activity of 230Pa in the sources was measured using a HPGe detector. The lavsan films were etched in NaOH solution and the etched films were scanned under an optical microscope. The exotic nuclear decay of 230U by emission of 22Ne was observed. A branching ratio relative to α decay was deduced, B =λNe/λα= (1.3±0.8)×10-14 for 22Ne emission from 230U.
基金the National High Technology Research and Development Programme of China(No.2002AA001028)the Tenth Five-year Industry Item of the Tackling Key Problem of Heilongjiang Province(No.CA02A201)
文摘A new method of using dynamic equalization technology to realize the maximum energy storage uti-lization was presented to overcome the influence of the disaccord among units of series super capacitor(SC) bank and ensure that the units could work safely.By considering in combination with the high spe-cific power,low working voltage,wide voltage working range and nonlinear external characteristics,wepresent constant duty ratio pulse frequency modulation mode and fuzzy control method based on state pre-diction in the active equalization circuit and accomplish the software and hardware design for the equaliza-tion system.The simulation analysis and experiment results of constant current multi-cycle and variablecurrent multi-cycle charge-discharge process verify the validity of the design.
文摘The conflict detection and resolution in collaborative design is a key issue to maintain multi disciplinary design consistency. This paper proposes a new method for conflict detection and resolution based on constraint satisfaction technique. The representation of design constraint, the interval arithmetic of the constraint satisfaction problem CSP and the conflict resolution strategy based on constraint relaxation and adjustment are introduced. A constraint satisfaction based conflict detection and resolution tool CSCDR is then developed. It can help collaborative designers to detect and resolve the conflicts in time in the early stage of the design process so that the unnecessary design iteration and repeated negotiation are avoided and the design efficiency is then much improved. A design case illustrates the effectiveness of CSCDR.
基金This project was partly supported by the National Natural Science Foundation of China and the grant NKBRSF G19990754.
文摘The Beijing Astronomical Observatory (BAO) 0.6 m telescope has been used for nearby supernova survey in more than 3000 fields, covering a total area of 235 deg2. More than 260000 CCD images have been collected since April 1996, with 45 supernovae discovered. We searched for variables in about 90000 images taken during 1996-1998. For the fields in which long period variables (LPVs) were discovered, we reduced further images taken from 1999 to 2000, for the period estimation. Among the 280000 stars selected from the survey fields, i.e., brighter than 18 mag, we discovered seven new LPVs and reconfirmed three known LPVs. Additionally, we found 146 variable star candidates, and reconfirmed about 20 previously known or suspected objects.
基金supported by National Natural Science Foundation of China (81371820)
文摘Dear Editor,In the late stages of the retroviral life cycle,the transcription of viral pre-m RNA is initiated at the 5′long terminal repeat(5′LTR)and terminated at the 3′LTR;the full-length and spliced viral RNAs are transported out of the nucleus and serve as templates for the translation of viral proteins or alternatively as the full-length viral genome to be packaged into virus particles.
文摘Objective: To observe the clinical effect of Yiqi Jianpi Bushen recipe (YQJPBS, 益气健脾补肾方) in antagonizing nephrotoxicity and hematological toxicity by cisplatin (CDDP). Methods: The patients with different types of carcinomas were divided into two groups. One group was treated by western medicine (WM), i.e. cisplatin combined with diuretic therapy. The other group by Chinese medicine (CM). One day before chemotherapy, YQJPBS was given orally. Urinary enzyme (NAG, γ-GT, ALP) and serum erythropoietin (Epo) were used as the key monitoring indicator. Results: The early renal damage by CDDP remains near proximal convoluted tubule, which leads to the rising of urinary enzyme. So urinary enzyme of the CM group was obviously lower than that of the WM group. The lesion of renal interstitial cells that produce Epo did not cause the serum Epo of WM group to rise obviously 15 days later. As a result there was 40% patients whose RBC and Hb became lower than the standard count. While serum Epo of CM group was higher than that of WM group, only 5% patients in the CM group had their RBC and Hb lowered. Conclusion: YQJPBS can effectively antagonize nephrotoxicity and hematological toxicity induced by CDDP.
