The solid-fueled thorium molten salt reactor(TMSR-SF1) is a 10 MW_(th) test reactor design to be deployed in 5-10 years by the TMSR group.Its design combines coated particle fuel and molten FLiBe coolant for great int...The solid-fueled thorium molten salt reactor(TMSR-SF1) is a 10 MW_(th) test reactor design to be deployed in 5-10 years by the TMSR group.Its design combines coated particle fuel and molten FLiBe coolant for great intrinsic safety features and economic advantages.Due to a large amount of beryllium in the coolant salt,photoneutrons are produced by(y,n) reaction,hence the increasing fraction of effective delayed neutrons in the core by the photoneutrons originating from the long-lived fission products.Some of the delayed photoneutron groups are of long lifetime,so a direct effect is resulted in the transient process and reactivity measurement.To study the impact of photoneutrons for TMSR-SF1,the effective photoneutron fraction is estimated using k-ratio method and performed by the Monte Carlo code(MCNP5) with ENDF/B-Ⅶ cross sections.Based on the coupled neutronphoton point kinetics equations,influence of the photoneutrons is analyzed.The results show that the impact of photoneutrons is not negligible in reactivity measurement.Without considering photoneutrons in on-line reactivity measurement based on inverse point kinetics can result in overestimation of the positive reactivity and underestimation of the negative reactivity.The photoneutrons also lead to more waiting time for the doubling time measurement.Since the photoneutron precursors take extremely long time to achieve equilibrium,a "steady" power operation may not directly imply a "real" criticality.展开更多
It is important to acquire the composition of Si1-xGex layer, especially that with high Ge content, epitaxied on Si substrate. Two nondestructive examination methods, double crystals X-ray diffraction （DCXRD） and mi...It is important to acquire the composition of Si1-xGex layer, especially that with high Ge content, epitaxied on Si substrate. Two nondestructive examination methods, double crystals X-ray diffraction （DCXRD） and micro-Raman measurement, were introduced comparatively to determine x value in Si1-xGex layer, which show that while the two methods are consistent with each other when x is low, the results obtained from double crystals X-ray diffraction are not credible due to the large strain relaxation occurring in Si1-xGex layers when Ge content is higher than about 20%. Micro-Raman measurement is more appropriate for determining high Ge content than DCXRD.展开更多
A measuring system for high-speed hydrogen ice pellet was introduced in this paper and the photographing of flying pellet taken therein. With the system, a pellet (minimum size of φ 0.3 mm) velocity (ranging from 50 ...A measuring system for high-speed hydrogen ice pellet was introduced in this paper and the photographing of flying pellet taken therein. With the system, a pellet (minimum size of φ 0.3 mm) velocity (ranging from 50 m/s to 2500 m/s) can be measured in the HL-1M tokamak fueling experiments. By analyzing photographs and the conditions of frozen pellets (including gas supply, gas replenishment, temperature controlling etc), the pellet-freezing technology is summarized in the paper.展开更多
The plasma rotation velocity were measured in HL-1M with Doppler shifts of CⅢ、 C Ⅱ、 O Ⅱ and H. line by a SKD high resolution spectrometer. The effects .of density' hydrogen pellet injection and carbon impuri...The plasma rotation velocity were measured in HL-1M with Doppler shifts of CⅢ、 C Ⅱ、 O Ⅱ and H. line by a SKD high resolution spectrometer. The effects .of density' hydrogen pellet injection and carbon impurities injected by laser-blow-off on toroidal(V) and poloidal (Vθ)rotation velocity have been observed. The Vθ measured from H. line is only half of that from C Ⅱ impurity line.展开更多
Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(...Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(2018)].They realized the self-testing of preparations and measurements in an N → 1(N ≥ 2) random access code(RAC), and provided robustness bounds in a 2 → 1 RAC.Since all N → 1 RACs with shared randomness are combinations of 2 → 1 and 3 → 1 RACs, the3 → 1 RAC is just as important as the 2 → 1 RAC.In this paper, we find a set of preparations and measurements in the3 → 1 RAC, and use them to complete the robustness self-testing analysis in the prepare-and-measure scenario.The method is robust to small but inevitable experimental errors.展开更多
This paper develops a novel distributed temperature measurement system based on DSP and DS18B20 digital thermometer. The real-time temperature of each node in the switchgear is obtained by several DS18B20s which are c...This paper develops a novel distributed temperature measurement system based on DSP and DS18B20 digital thermometer. The real-time temperature of each node in the switchgear is obtained by several DS18B20s which are connected on the 1-wire bus together. RS-485 master-slave communication protocol is used to centralize monitoring temperatures of several switchgear cabinets. The system also has the function of temperature alarm. The operation of simulation experiment has showed that the system is able to complete monitoring real-time temperatures in high voltage switchgear.展开更多
Objectives: this research was conducted to describe the ultrasonic measurements of the foot full measurements (FFM) and their importance in the antenatal care (ANC). Material and methods: the Descriptive quantitative ...Objectives: this research was conducted to describe the ultrasonic measurements of the foot full measurements (FFM) and their importance in the antenatal care (ANC). Material and methods: the Descriptive quantitative cross-sectional study conducted in the ultrasound department at Alshaekh Mohammed Ali Fadol hospital in Omdurman locality. The study included 400 healthy Sudanese pregnant women whom in the 1st (late), 2nd and 3rd trimesters (i.e., after 10 weeks gestational age) of different parity and ages (15 years old and above);they have regular menstrual cycle and well certain of their last menstrual period and calculated date of delivery. Ultrasonographic measurement of Full Foot Length1 (FFL1), Foot Full Length2 (FFL2), and Foot Full Width (FFW) of all pregnant women were done. Sonographically we measured fetal foot from 14 to 40 weeks of gestation. Results: the study revealed that the mean FFL1 was 58.7 ± 12.9 mm. The minimum measurement was 18.8 mm, and the maximum was 89.1 mm, while the mean value of FFL2 was 53.4 ± 11.4 mm, with minimum value 17.5 mm and maximum 81.7 mm, and the mean FFW was 23.7 ± 5.1 mm, with minimum value 7.0 mm and maximum 38.0 mm. Conclusion: a strongly significant relationships were observed between (FFL1, FFL2, FFW) and gestational age (p = 0.00). However there is no significant difference between the FFL1, FFL2, and correlations with sex of embryo, residence, occupation, parity, maternal height, socioeconomic status, bleeding during this pregnancy, chronic illness, and caesarian section, moreover there are significant correlations between the FFL1, FFL2 and the (maternal age, maternal weight, and body mass index), but in the measurement of the fetal FFW there were no significant correlations with (sex of embryo, maternal age, body mass index, residence, occupation, parity, socioeconomic status, bleeding during this pregnancy, chronic illness, and caesarian section). Also there are significant correlations between the FFW and the maternal weight and height.展开更多
BACKGROUND Alpha-1 antitrypsin deficiency(AATD)is a codominant autosomal hereditary condition that predisposes patients to the development of lung and/or liver disease,and Pi*Z allele is the most clinically relevant m...BACKGROUND Alpha-1 antitrypsin deficiency(AATD)is a codominant autosomal hereditary condition that predisposes patients to the development of lung and/or liver disease,and Pi*Z allele is the most clinically relevant mutation.AIM To evaluate the impact of clinical parameters and AATD phenotypes,particularly the Pi*Z allele,in liver fibrosis.METHODS Cross-sectional cohort study including consecutive patients with AATD followed in Pulmonology or Hepatology consultation.RESULTS Included 69 patients,49.3%had Pi*MZ phenotype and 10.1%Pi*ZZ.An age≥55 years,age at diagnosis≥41 years and AAT at diagnosis<77 mg/dL predicted a nonalcoholic fatty liver disease fibrosis score(NFS)not excluding advanced fibrosis[area under the curve(AUC)=0.840,P<0.001;AUC=0.836,P<0.001;AUC=0.681,P=0.025].An age≥50 years and age at diagnosis≥41 years predicted a fibrosis-4 index of moderate to advanced fibrosis(AUC=0.831,P<0.001;AUC=0.795,P<0.001).Patients with hypertension,type 2 diabetes mellitus(DM),dyslipidaemia,metabolic syndrome,and regular alcohol consumption were more likely to have a NFS not excluding advanced fibrosis(P<0.001,P=0.002,P=0.008,P<0.001,P=0.033).Patients with at least one Pi*Z allele and type 2 DM were 8 times more likely to have liver stiffness measurement≥7.1 kPa(P=0.040).CONCLUSION Risk factors for liver disease in AATD included an age≥50 years,age at diagnosis≥41 years,metabolic risk factors,regular alcohol consumption,at least one Pi*Z allele,and AAT value at diagnosis<77 mg/dL.We created an algorithm for liver disease screening in AATD patients to use in primary care,selecting those to be referred to Hepatology consultation.展开更多
基金supported by the "Strategic Priority Research Program" of the Chinese Academy of Sciences(No.XDA02010000)the Frontier Science Key Program of the Chinese Academy of Sciences(No.QYZDY-SSW-JSC016)
文摘The solid-fueled thorium molten salt reactor(TMSR-SF1) is a 10 MW_(th) test reactor design to be deployed in 5-10 years by the TMSR group.Its design combines coated particle fuel and molten FLiBe coolant for great intrinsic safety features and economic advantages.Due to a large amount of beryllium in the coolant salt,photoneutrons are produced by(y,n) reaction,hence the increasing fraction of effective delayed neutrons in the core by the photoneutrons originating from the long-lived fission products.Some of the delayed photoneutron groups are of long lifetime,so a direct effect is resulted in the transient process and reactivity measurement.To study the impact of photoneutrons for TMSR-SF1,the effective photoneutron fraction is estimated using k-ratio method and performed by the Monte Carlo code(MCNP5) with ENDF/B-Ⅶ cross sections.Based on the coupled neutronphoton point kinetics equations,influence of the photoneutrons is analyzed.The results show that the impact of photoneutrons is not negligible in reactivity measurement.Without considering photoneutrons in on-line reactivity measurement based on inverse point kinetics can result in overestimation of the positive reactivity and underestimation of the negative reactivity.The photoneutrons also lead to more waiting time for the doubling time measurement.Since the photoneutron precursors take extremely long time to achieve equilibrium,a "steady" power operation may not directly imply a "real" criticality.
基金This work is supported by the National Natural Science Foundation of China （Grant Nos. 60336010 ＆ 90401001）973 Program （Grant No. TG 2000036603）the Student Innovation Program of CAS （No. 1731000500010）.
文摘It is important to acquire the composition of Si1-xGex layer, especially that with high Ge content, epitaxied on Si substrate. Two nondestructive examination methods, double crystals X-ray diffraction （DCXRD） and micro-Raman measurement, were introduced comparatively to determine x value in Si1-xGex layer, which show that while the two methods are consistent with each other when x is low, the results obtained from double crystals X-ray diffraction are not credible due to the large strain relaxation occurring in Si1-xGex layers when Ge content is higher than about 20%. Micro-Raman measurement is more appropriate for determining high Ge content than DCXRD.
文摘A measuring system for high-speed hydrogen ice pellet was introduced in this paper and the photographing of flying pellet taken therein. With the system, a pellet (minimum size of φ 0.3 mm) velocity (ranging from 50 m/s to 2500 m/s) can be measured in the HL-1M tokamak fueling experiments. By analyzing photographs and the conditions of frozen pellets (including gas supply, gas replenishment, temperature controlling etc), the pellet-freezing technology is summarized in the paper.
文摘The plasma rotation velocity were measured in HL-1M with Doppler shifts of CⅢ、 C Ⅱ、 O Ⅱ and H. line by a SKD high resolution spectrometer. The effects .of density' hydrogen pellet injection and carbon impurities injected by laser-blow-off on toroidal(V) and poloidal (Vθ)rotation velocity have been observed. The Vθ measured from H. line is only half of that from C Ⅱ impurity line.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61572081,61672110,and 61671082)
文摘Recently, Tavakoli et al.proposed a self-testing scheme in the prepare-and-measure scenario, showing that self-testing is not necessarily based on entanglement and violation of a Bell inequality [Phys.Rev.A 98 062307(2018)].They realized the self-testing of preparations and measurements in an N → 1(N ≥ 2) random access code(RAC), and provided robustness bounds in a 2 → 1 RAC.Since all N → 1 RACs with shared randomness are combinations of 2 → 1 and 3 → 1 RACs, the3 → 1 RAC is just as important as the 2 → 1 RAC.In this paper, we find a set of preparations and measurements in the3 → 1 RAC, and use them to complete the robustness self-testing analysis in the prepare-and-measure scenario.The method is robust to small but inevitable experimental errors.
文摘This paper develops a novel distributed temperature measurement system based on DSP and DS18B20 digital thermometer. The real-time temperature of each node in the switchgear is obtained by several DS18B20s which are connected on the 1-wire bus together. RS-485 master-slave communication protocol is used to centralize monitoring temperatures of several switchgear cabinets. The system also has the function of temperature alarm. The operation of simulation experiment has showed that the system is able to complete monitoring real-time temperatures in high voltage switchgear.
文摘Objectives: this research was conducted to describe the ultrasonic measurements of the foot full measurements (FFM) and their importance in the antenatal care (ANC). Material and methods: the Descriptive quantitative cross-sectional study conducted in the ultrasound department at Alshaekh Mohammed Ali Fadol hospital in Omdurman locality. The study included 400 healthy Sudanese pregnant women whom in the 1st (late), 2nd and 3rd trimesters (i.e., after 10 weeks gestational age) of different parity and ages (15 years old and above);they have regular menstrual cycle and well certain of their last menstrual period and calculated date of delivery. Ultrasonographic measurement of Full Foot Length1 (FFL1), Foot Full Length2 (FFL2), and Foot Full Width (FFW) of all pregnant women were done. Sonographically we measured fetal foot from 14 to 40 weeks of gestation. Results: the study revealed that the mean FFL1 was 58.7 ± 12.9 mm. The minimum measurement was 18.8 mm, and the maximum was 89.1 mm, while the mean value of FFL2 was 53.4 ± 11.4 mm, with minimum value 17.5 mm and maximum 81.7 mm, and the mean FFW was 23.7 ± 5.1 mm, with minimum value 7.0 mm and maximum 38.0 mm. Conclusion: a strongly significant relationships were observed between (FFL1, FFL2, FFW) and gestational age (p = 0.00). However there is no significant difference between the FFL1, FFL2, and correlations with sex of embryo, residence, occupation, parity, maternal height, socioeconomic status, bleeding during this pregnancy, chronic illness, and caesarian section, moreover there are significant correlations between the FFL1, FFL2 and the (maternal age, maternal weight, and body mass index), but in the measurement of the fetal FFW there were no significant correlations with (sex of embryo, maternal age, body mass index, residence, occupation, parity, socioeconomic status, bleeding during this pregnancy, chronic illness, and caesarian section). Also there are significant correlations between the FFW and the maternal weight and height.
文摘BACKGROUND Alpha-1 antitrypsin deficiency(AATD)is a codominant autosomal hereditary condition that predisposes patients to the development of lung and/or liver disease,and Pi*Z allele is the most clinically relevant mutation.AIM To evaluate the impact of clinical parameters and AATD phenotypes,particularly the Pi*Z allele,in liver fibrosis.METHODS Cross-sectional cohort study including consecutive patients with AATD followed in Pulmonology or Hepatology consultation.RESULTS Included 69 patients,49.3%had Pi*MZ phenotype and 10.1%Pi*ZZ.An age≥55 years,age at diagnosis≥41 years and AAT at diagnosis<77 mg/dL predicted a nonalcoholic fatty liver disease fibrosis score(NFS)not excluding advanced fibrosis[area under the curve(AUC)=0.840,P<0.001;AUC=0.836,P<0.001;AUC=0.681,P=0.025].An age≥50 years and age at diagnosis≥41 years predicted a fibrosis-4 index of moderate to advanced fibrosis(AUC=0.831,P<0.001;AUC=0.795,P<0.001).Patients with hypertension,type 2 diabetes mellitus(DM),dyslipidaemia,metabolic syndrome,and regular alcohol consumption were more likely to have a NFS not excluding advanced fibrosis(P<0.001,P=0.002,P=0.008,P<0.001,P=0.033).Patients with at least one Pi*Z allele and type 2 DM were 8 times more likely to have liver stiffness measurement≥7.1 kPa(P=0.040).CONCLUSION Risk factors for liver disease in AATD included an age≥50 years,age at diagnosis≥41 years,metabolic risk factors,regular alcohol consumption,at least one Pi*Z allele,and AAT value at diagnosis<77 mg/dL.We created an algorithm for liver disease screening in AATD patients to use in primary care,selecting those to be referred to Hepatology consultation.
