Traditional spectrophotometers have a large volume and slow scanning speed,which limits their applicability for rapid on-site detection.Herein,a micro-spectrophotometer(named ATOM)is fabricated,and its performance is ...Traditional spectrophotometers have a large volume and slow scanning speed,which limits their applicability for rapid on-site detection.Herein,a micro-spectrophotometer(named ATOM)is fabricated,and its performance is verified in water quality testing.An M-type Czerny-Turner light path structure,a broadband light emitting diode(LED)light source,and a linear charge-coupled device(CCD)photodetector were adopted in ATOM.The performance of ATOM was validated through iron content determination by using o-phenanthroline spectrophotometry.The experiment results showed that the linear correlation coefficient of determination R^(2) was 0.9997 for mass concentrations ranging from 0 to 2.0μg/mL.The relative standard deviation was 0.37%,and the relative error compared to a commercial large-scale spectrophotometer was below 1.4%.The dimensions of ATOM are 75 mm×60 mm×25 mm,with hardware costs of approximately 1000 CNY.ATOM features compact size,low cost,rapid measurement,high integration and high precision,making it suitable for portable on-site rapid detection.展开更多
The water drop penetration time(WDPT)test consists of placing water drops on a material's surface in order to evaluate how long it takes to penetrate the pores.It is used to evaluate the hydrophobicity of material...The water drop penetration time(WDPT)test consists of placing water drops on a material's surface in order to evaluate how long it takes to penetrate the pores.It is used to evaluate the hydrophobicity of materials.This study aims at investigating in more detail the soil-water interaction during the test,exposing its mechanism.For that,a model soil named Hamburg Sand was coated with a hydrophobic fluoropolymer and then a WDPT test was performed while computed tomography(CT)images were taken.Tomography experiments were performed at the P07 high-energy materials science(HEMS)beamline,operated by Helmholtz–Zentrum Hereon,at the storage ring PETRA III at the Deutsches Elektronen-Synchrotron(DESY)in Hamburg.Using synchrotron radiation,a tomogram can be obtained in about 10 min,way less time than regular laboratory X-ray sources usually owned by universities.The faster imaging enables the observation of the drop penetration during time and thus provides insight into the dynamics of the process.After that,digital discrete image correlation is performed to track the displacement of the grains throughout time.From the results one can observe that,as the drop is absorbed at the material's surface,the grains directly around the droplet base are dragged to the liquid-air interface around the drop,revealing grain kinematics during capillary interactions of the penetrating liquid and sand grains.展开更多
The shear strength parameters for geotechnical designs are obtained mainly from consolidated drained (CD) or consolidated undrained (CU) triaxial tests. However, during construction, the excess pore-air pressure g...The shear strength parameters for geotechnical designs are obtained mainly from consolidated drained (CD) or consolidated undrained (CU) triaxial tests. However, during construction, the excess pore-air pressure generally dissipates instantaneously while the excess pore-water pressure dissipates with time. This condition needs to be simulated in a constant water content (CW) triaxial test. The study on Yunnan red clay is carried out to investigate the soil-water characteristics and the shear strength characteristics under the constant water content condition. Osmotic technique is used to obtain the soil-water characteristic curve. A series of CW triaxial tests are conducted on statically compacted specimens. The experimental results show that the soil-water characteristic curve has a low air entry value of 7 kPa due to large pores in non-uniform pore size distribution, and a high residual value exceeding 10 MPa. In addition, the initial degree of saturation and net confining stress play an important role in affecting the shear characteristics under the constant water content condition. Finally, a new semi-empirical shear strength model in terms of degree of saturation is proposed and then applied to Yuunan red clay. Simulation result shows that the model is capable of capturing some key features of soils. The model can be used in whole engineering practice range, covering both unsaturmed and saturated soils.展开更多
BACKGROUND: It has been demonstrated that patients with functional dyspepsia have experiences social life stress events, and accompanied by psychological disorders, mainly manifested as depression and anxiety.Mental ...BACKGROUND: It has been demonstrated that patients with functional dyspepsia have experiences social life stress events, and accompanied by psychological disorders, mainly manifested as depression and anxiety.Mental factors can lead to excessive gastrointestinal consensual reaction, and result in different brain-gut axis disturbance, and then cause the gastrointestinal sensorimotor abnormality and endocrine changes.OBJECTIVE: To observe the effect of antidepressant treatment on the changes of water load and serum cortisol in patients with functional dyspepsia, and analyze the therapeutic mechanism.DESIGN: A comparative observation.SETTING: The First Affiliated Hospital o Zhengzhou University.PARTICIPANTS: Forty-five patients with functional dyspepsia accompanied by depression were selected from the Department of Gastroenterology, the First Affiliated Hospital of Zhengzhou University from July 2004 to July 2006, and they were 25 - 65 years of age, and their disease courses ranged 1 - 10 years. They were all accorded with the diagnostic standards for Rome Ⅱ functional dyspepsia functional dyspepsia. As the patients' will, they were divided into treatment group (n =30, 12 males and 18 females) and control group (n =15, 6 males and 9 females), and there were no significant differences in the data between the two groups (P 〉 0.05). The programs were discussed and agreed by the committee of medical ethics of the First Affiliated Hospital of Zhengzhou University. Informed contents were obtained from all the patients.METHODS: In the treatment group, the patients were treated with venlafaxine sustained release capsule (75 mg per day), and those with sleep disorder were added by benzodiazepines (alprazolam). In the control group, the patients were given routine treatments of antacid, prokinetics, etc. Before and after 8-week treatment, the following examinations were performed: ① The gastrointestinal symptoms were assessed according to the symptoms; ② The severity of depression was evaluated with Hamilton depression scale (HAMD); ③The relaxation of proximal stomach was observed using water load test; ④ The serum level of cortisol was detected.MAIN OUTCOME MEASURES: ① Symptom score; ② HAMD score; ③ Water load amount; ④Serum level of cortisol.RESULTS: All the 45 patients were involved in the analysis of results. ① Symptom score: The scores of gastrointestinal symptoms were decreased as compared with those before treatment in both the treatment group and control group (P 〈 0.05). ② HAMD scores: The scores of HAMD were decreased as compared with those before treatment in both the treatment group and control group (P 〈 0.05). ③ Water load amount:The total effective rate was significantly higher in the treatment group than the control group (P 〈 0.05). ④The serum levels of cortisol after treatment were significantly lower than those before treatment in the patients with severe gastrointestinal symptoms in the treatment group and control group (P 〈 0.05).CONCLUSION: Antidepressants can normalize the cortisol level of patients with functional dyspepsia, and then decrease gastric sensitivity and ameliorates the receptive relaxation of proximal stomach, also increase the water load amount correspondingly, and finally control the gastrointestinal symptoms of functional dyspepsia.展开更多
Biogas is a kind of regenerable energy which is inexpensive and friendly to the environment, but the potential ofbiogas is difficult to develop fully in China, for most biogas have badly qualities and the utilization ...Biogas is a kind of regenerable energy which is inexpensive and friendly to the environment, but the potential ofbiogas is difficult to develop fully in China, for most biogas have badly qualities and the utilization of it is monotonous. The suitable operation term about biogas upgrading by pressurized water scrubbing was researched through the orthogonal test in this study. Two sorts of scrubber packing included the random multidimensional hollow sphere packing and the structured screen packing were also used, and the effects of experiment factors included packing, water temperature, gas flow speed, water flow speed and washing pressure were studied. The results showed that better effect was got when the screen structured packing was used; all the five test factors affected the processing significantly in the arrange as before and had better and better significant effects.展开更多
AIM: Recently, drinking load tests with water or nutritional beverages have been proposed as diagnostic tools for functional dyspepsia (FD), therefore we sought to reproduce if these tests can discriminate between FD ...AIM: Recently, drinking load tests with water or nutritional beverages have been proposed as diagnostic tools for functional dyspepsia (FD), therefore we sought to reproduce if these tests can discriminate between FD patients and controls in a Mexican population. METHODS: Twenty FD-Rome Ⅱ patients were matched by age and gender with 20 healthy controls. All underwent both drinking tests at a 15 mL/min rate, randomly, 7 d apart. Every 5 min within each test, four symptoms were evaluated (satiety, bloating, nausea and pain) by Likert scales. Maximum tolerated volume (MTV) was defined as the ingested volume when a score of 5 was reached for any symptom or when the test had to be stopped because the patients could not tolerate more volume. Sensitivity and specificity were analyzed. RESULTS: FD patients had higher symptom scores for both tests compared to controls (water: t= 4.1, P= 0.001 <0.01; Nutren(R): t= 5.2, P= 0.001<0.01). The MTV forwater and Nutren(R) were significantly lower in FD (water: 1014±288 vs 1749±275 mL; t = 7.9, P = 0.001<0.01;Nutren(R): 652±168 vs 1278±286 mL; t= 6.7, P = 0.001<0.01). With the volume tolerated by the controls, the percentile 10 was determined as the lower limit fortolerance. Sensitivity and specificity were 0.90, 0.95 for water and 0.95, 0.95 for Nutren(R) tests.CONCLUSION: A drinking test with water or a nutritional beverage can discriminate between FD patients and healthy subjects in Mexico, with high sensitivity and specificity. These tests could be used as objective, noninvasive, and safe diagnostic approaches for FD patients.展开更多
In this paper, an inner turret moored FPSO which works in the water of 320 m depth, is selected to study the socalled "passively-truncated + numerical-simulation" type of hybrid model testing technique while the tn...In this paper, an inner turret moored FPSO which works in the water of 320 m depth, is selected to study the socalled "passively-truncated + numerical-simulation" type of hybrid model testing technique while the tnmcated water depth is 160 m and the model scale ), = 80. During the investigation, the optimization design of the equivalent-depth truncated system is performed by using the similarity of the static characteristics between the truncated system and the full depth one as the objective function. According to the truncated system, the corresponding physical test model is made. By adopting the coupling time domain simulation method, the tnmcated system model test is numerically reconstructed to carefully verify the computer simulation software and to adjust the corresponding hydrodynamic parameters. Based on the above work, the numerical extrapolation to the full depth system is performed by using the verified computer software and the adjusted hydrodyrmmic parameters. The full depth system model test is then performed in the basin and the results are compared with those from the numerical extrapolation. At last, the implementation procedure and the key technique of the hybrid model testing of the deep-sea platforms are summarized and printed. Through the above investigations, some beneficial conclusions are presented.展开更多
AIM:To compare the impact of the right recumbent position with the sitting position on gastric emptying of water. METHODS:In eight healthy male volunteers,the 13C acetate breath test was performed twice to assess gast...AIM:To compare the impact of the right recumbent position with the sitting position on gastric emptying of water. METHODS:In eight healthy male volunteers,the 13C acetate breath test was performed twice to assess gastric emptying of 100 mL tap water.Subjects were seated in one test and lying on their right side in the other.In both positions,pulmonary 13CO2 exhalation curves were obtained by plotting breath data against time.Percent gastric retention curves were created by analyzing data using the Wagner-Nelson protocol. RESULTS:No significant posture effect was found in pulmonary 13CO2 output curves(P=0.2150),whereas a significant effect was seen in gastric retention curves (P=0.0315).The percent retention values at 10 min and 15 min were significantly smaller when subjects were in the right recumbent position compared with the seated position(P<0.05).Our results verified the accelerating effect of the right recumbent position on gastric emptying of non-nutritive solutions.Concerning clinical implications,this study suggests that placing patients with acute pain on their right side after oral administration of analgesic drugs in solution is justified as an effective practice for rapid pain relief.For patients with gastrointestinal reflux symptoms,sleeping in the right recumbent position may reduce nocturnal symptoms,as delayed gastric emptying can cause reflux symptoms. CONCLUSION:Gastric emptying of water occurs more quickly when a subject lies on the right side compared with sitting.展开更多
This paper introduces model test results of water pressure in a fault, which is located in a slope and 16 different conditions. The results show that the water pressures in fault can be expressed by a linear function,...This paper introduces model test results of water pressure in a fault, which is located in a slope and 16 different conditions. The results show that the water pressures in fault can be expressed by a linear function, which is similar to the theoretical model suggested by Hoek. Factors affecting water pressures are water level in tension crack, dip angle of fault, the height of filling materials and thickness of fault zone in sequence.展开更多
Many landslides in reservoir areas continuously deform under cyclic water level fluctuations due to reservoir operations. In this paper,a landslide model, developed for a typical colluvial landslide in the Three Gorge...Many landslides in reservoir areas continuously deform under cyclic water level fluctuations due to reservoir operations. In this paper,a landslide model, developed for a typical colluvial landslide in the Three Gorges Reservoir area, is used to study the effect of cyclic water level fluctuations on the landslide. Five cyclic water level fluctuations were implemented in the test, and the fluctuation rate in the last two fluctuations doubled over the first three fluctuations. The pore water pressure and lateral landslide profiles were obtained during the test. A measurement of the landslide soil loss was proposed to quantitatively evaluate the influence of water level fluctuations. The test results show that the first water level rising is most negative to the landslide among the five cycles. The fourth drawdown with a higher drawdown rate caused further large landslide deformation. An increase of the water level drawdown rate is much more unfavorable to the landslide than an increase of the water level rising rate. In addition, the landslide was found to have an adaptive ability to resist subsequent water level fluctuations after undergoing large deformation during a water level fluctuation. The landslide deformation and observations in the field were found to support the test results well.展开更多
With the rapid economic development and the continuous improvement of peoples living standards, ensuring the safety of water supply has become an urgent task. The national requirements for water quality indicators are...With the rapid economic development and the continuous improvement of peoples living standards, ensuring the safety of water supply has become an urgent task. The national requirements for water quality indicators are becoming more and more stringent, and water quality testing is a process of evaluating water quality. By analyzing the results of water quality testing, water quality can be judged and dealt with accordingly. Starting from the direction of improving the accuracy and stability of water quality testing, this paper focuses on analyzing some of the reasons, and puts forward some suggestions on improving the accuracy and stability of water quality testing.展开更多
From the birth of life, water is the source of life, and its quality is closely related to people's daily life. Therefore, water quality testing is particularly important. Therefore, relevant staff must pay attent...From the birth of life, water is the source of life, and its quality is closely related to people's daily life. Therefore, water quality testing is particularly important. Therefore, relevant staff must pay attention to water quality testing to ensure that the water quality of drinking water can meet the requirements of relevant standards. In recent years, the application of environmental information technology and big data technology in water quality monitoring has improved the use efficiency of environmental monitoring equipment. The application of intelligent and automatic water quality detection system can realize continuous detection of water quality, and can also quickly detect sudden changes in water quality inside the reservoir, so as to provide more accurate data support for water quality detection, water source protection and environmental protection. Therefore, water quality testing methods should be continuously optimized and adjusted to make them more scientific and perfect, and to provide more accurate drinking water quality testing data for residents.展开更多
With the continuous development of China's economy and society, people gradually improve the requirements of water quality, constantly pay attention to the water quality test results, water resources not only meet...With the continuous development of China's economy and society, people gradually improve the requirements of water quality, constantly pay attention to the water quality test results, water resources not only meet People's Daily drinking, and social production and life is widely used. Rapid and accurate water quality testing can not only reflect the current situation of the water environment, but also for water environment management and pollution source control and leadership decision-making at all levels to provide an important scientific basis, but also through the water quality testing results for the relevant statistical analysis, control the water quality change law, and then improve the water quality. When people drink substandard water, it will not only cause waste of water resources, but also cause harm to people's health. In order to respond to the sustainable development strategy put forward by the country and improve people's living standards, improving water quality is an inevitable choice, and water quality detection is the prerequisite for improving water quality.展开更多
This paper discusses the monitoring section layout, sampling point layout, sampling time and sampling frequency determination, preparation before water sample collection, collection method, collector, industrial sewag...This paper discusses the monitoring section layout, sampling point layout, sampling time and sampling frequency determination, preparation before water sample collection, collection method, collector, industrial sewage collection, flow determination, water sample transportation and the whole process of river water quality control.展开更多
Water vapor monitoring system by Beidou satellite is a new detection system in meteorological department, which makes receiving amount of detected data and data storage and transmission pressure increase. Here, we try...Water vapor monitoring system by Beidou satellite is a new detection system in meteorological department, which makes receiving amount of detected data and data storage and transmission pressure increase. Here, we try to use data compression to relieve pressure. Compres- sion software of water vapor monitoring system by Beidou satellite can be designed into three components: real-time compression software, check compression software and manual compression software, which respectively completes the compression tasks under real-time receiving, in-time check and separate compression, thereby forming a perfect compression system. Taking the design of manual compression software as guide,and using c language to develop,compression test of original receiving data is conducted. Test result proves that the system can carry out batch auto- matic compression, and compression rate can reach 30% ,which can reach the target of saving space in a degree.展开更多
During deep water oil well testing, the low temperature environment is easy to cause wax precipitation, which affects the normal operation of the test and increases operating costs and risks. Therefore, a numerical me...During deep water oil well testing, the low temperature environment is easy to cause wax precipitation, which affects the normal operation of the test and increases operating costs and risks. Therefore, a numerical method for predicting the wax precipitation region in oil strings was proposed based on the temperature and pressure fields of deep water test string and the wax precipitation calculation model. And the factors affecting the wax precipitation region were analyzed. The results show that: the wax precipitation region decreases with the increase of production rate, and increases with the decrease of geothermal gradient, increase of water depth and drop of water-cut of produced fluid, and increases slightly with the increase of formation pressure. Due to the effect of temperature and pressure fields, wax precipitation region is large in test strings at the beginning of well production. Wax precipitation region gradually increases with the increase of shut-in time. These conclusions can guide wax prevention during the testing of deep water oil well, to ensure the success of the test.展开更多
基金National Natural Science Foundation of China(No.62375048)Natural Science Foundation of Shanghai,China(No.22ZR1402600。
文摘Traditional spectrophotometers have a large volume and slow scanning speed,which limits their applicability for rapid on-site detection.Herein,a micro-spectrophotometer(named ATOM)is fabricated,and its performance is verified in water quality testing.An M-type Czerny-Turner light path structure,a broadband light emitting diode(LED)light source,and a linear charge-coupled device(CCD)photodetector were adopted in ATOM.The performance of ATOM was validated through iron content determination by using o-phenanthroline spectrophotometry.The experiment results showed that the linear correlation coefficient of determination R^(2) was 0.9997 for mass concentrations ranging from 0 to 2.0μg/mL.The relative standard deviation was 0.37%,and the relative error compared to a commercial large-scale spectrophotometer was below 1.4%.The dimensions of ATOM are 75 mm×60 mm×25 mm,with hardware costs of approximately 1000 CNY.ATOM features compact size,low cost,rapid measurement,high integration and high precision,making it suitable for portable on-site rapid detection.
基金funding of this research by the German Research Foundation(Deutsche Forschungsgemeinschaft,DFG)in the framework of Research Training Group GRK 2462:Processes in natural and technical Particle-Fluid-Systems at Hamburg University of Technology(TUHH).
文摘The water drop penetration time(WDPT)test consists of placing water drops on a material's surface in order to evaluate how long it takes to penetrate the pores.It is used to evaluate the hydrophobicity of materials.This study aims at investigating in more detail the soil-water interaction during the test,exposing its mechanism.For that,a model soil named Hamburg Sand was coated with a hydrophobic fluoropolymer and then a WDPT test was performed while computed tomography(CT)images were taken.Tomography experiments were performed at the P07 high-energy materials science(HEMS)beamline,operated by Helmholtz–Zentrum Hereon,at the storage ring PETRA III at the Deutsches Elektronen-Synchrotron(DESY)in Hamburg.Using synchrotron radiation,a tomogram can be obtained in about 10 min,way less time than regular laboratory X-ray sources usually owned by universities.The faster imaging enables the observation of the drop penetration during time and thus provides insight into the dynamics of the process.After that,digital discrete image correlation is performed to track the displacement of the grains throughout time.From the results one can observe that,as the drop is absorbed at the material's surface,the grains directly around the droplet base are dragged to the liquid-air interface around the drop,revealing grain kinematics during capillary interactions of the penetrating liquid and sand grains.
基金Project(51068002) supported by the National Natural Science Foundation of ChinaProject(10-046-14-1) supported by Guangxi Key Laboratory of Geomechanics and Geotechnical Engineering,China
文摘The shear strength parameters for geotechnical designs are obtained mainly from consolidated drained (CD) or consolidated undrained (CU) triaxial tests. However, during construction, the excess pore-air pressure generally dissipates instantaneously while the excess pore-water pressure dissipates with time. This condition needs to be simulated in a constant water content (CW) triaxial test. The study on Yunnan red clay is carried out to investigate the soil-water characteristics and the shear strength characteristics under the constant water content condition. Osmotic technique is used to obtain the soil-water characteristic curve. A series of CW triaxial tests are conducted on statically compacted specimens. The experimental results show that the soil-water characteristic curve has a low air entry value of 7 kPa due to large pores in non-uniform pore size distribution, and a high residual value exceeding 10 MPa. In addition, the initial degree of saturation and net confining stress play an important role in affecting the shear characteristics under the constant water content condition. Finally, a new semi-empirical shear strength model in terms of degree of saturation is proposed and then applied to Yuunan red clay. Simulation result shows that the model is capable of capturing some key features of soils. The model can be used in whole engineering practice range, covering both unsaturmed and saturated soils.
文摘BACKGROUND: It has been demonstrated that patients with functional dyspepsia have experiences social life stress events, and accompanied by psychological disorders, mainly manifested as depression and anxiety.Mental factors can lead to excessive gastrointestinal consensual reaction, and result in different brain-gut axis disturbance, and then cause the gastrointestinal sensorimotor abnormality and endocrine changes.OBJECTIVE: To observe the effect of antidepressant treatment on the changes of water load and serum cortisol in patients with functional dyspepsia, and analyze the therapeutic mechanism.DESIGN: A comparative observation.SETTING: The First Affiliated Hospital o Zhengzhou University.PARTICIPANTS: Forty-five patients with functional dyspepsia accompanied by depression were selected from the Department of Gastroenterology, the First Affiliated Hospital of Zhengzhou University from July 2004 to July 2006, and they were 25 - 65 years of age, and their disease courses ranged 1 - 10 years. They were all accorded with the diagnostic standards for Rome Ⅱ functional dyspepsia functional dyspepsia. As the patients' will, they were divided into treatment group (n =30, 12 males and 18 females) and control group (n =15, 6 males and 9 females), and there were no significant differences in the data between the two groups (P 〉 0.05). The programs were discussed and agreed by the committee of medical ethics of the First Affiliated Hospital of Zhengzhou University. Informed contents were obtained from all the patients.METHODS: In the treatment group, the patients were treated with venlafaxine sustained release capsule (75 mg per day), and those with sleep disorder were added by benzodiazepines (alprazolam). In the control group, the patients were given routine treatments of antacid, prokinetics, etc. Before and after 8-week treatment, the following examinations were performed: ① The gastrointestinal symptoms were assessed according to the symptoms; ② The severity of depression was evaluated with Hamilton depression scale (HAMD); ③The relaxation of proximal stomach was observed using water load test; ④ The serum level of cortisol was detected.MAIN OUTCOME MEASURES: ① Symptom score; ② HAMD score; ③ Water load amount; ④Serum level of cortisol.RESULTS: All the 45 patients were involved in the analysis of results. ① Symptom score: The scores of gastrointestinal symptoms were decreased as compared with those before treatment in both the treatment group and control group (P 〈 0.05). ② HAMD scores: The scores of HAMD were decreased as compared with those before treatment in both the treatment group and control group (P 〈 0.05). ③ Water load amount:The total effective rate was significantly higher in the treatment group than the control group (P 〈 0.05). ④The serum levels of cortisol after treatment were significantly lower than those before treatment in the patients with severe gastrointestinal symptoms in the treatment group and control group (P 〈 0.05).CONCLUSION: Antidepressants can normalize the cortisol level of patients with functional dyspepsia, and then decrease gastric sensitivity and ameliorates the receptive relaxation of proximal stomach, also increase the water load amount correspondingly, and finally control the gastrointestinal symptoms of functional dyspepsia.
基金Supported by National Science and Technology Supporting Plan (2008BADC4B02)
文摘Biogas is a kind of regenerable energy which is inexpensive and friendly to the environment, but the potential ofbiogas is difficult to develop fully in China, for most biogas have badly qualities and the utilization of it is monotonous. The suitable operation term about biogas upgrading by pressurized water scrubbing was researched through the orthogonal test in this study. Two sorts of scrubber packing included the random multidimensional hollow sphere packing and the structured screen packing were also used, and the effects of experiment factors included packing, water temperature, gas flow speed, water flow speed and washing pressure were studied. The results showed that better effect was got when the screen structured packing was used; all the five test factors affected the processing significantly in the arrange as before and had better and better significant effects.
文摘AIM: Recently, drinking load tests with water or nutritional beverages have been proposed as diagnostic tools for functional dyspepsia (FD), therefore we sought to reproduce if these tests can discriminate between FD patients and controls in a Mexican population. METHODS: Twenty FD-Rome Ⅱ patients were matched by age and gender with 20 healthy controls. All underwent both drinking tests at a 15 mL/min rate, randomly, 7 d apart. Every 5 min within each test, four symptoms were evaluated (satiety, bloating, nausea and pain) by Likert scales. Maximum tolerated volume (MTV) was defined as the ingested volume when a score of 5 was reached for any symptom or when the test had to be stopped because the patients could not tolerate more volume. Sensitivity and specificity were analyzed. RESULTS: FD patients had higher symptom scores for both tests compared to controls (water: t= 4.1, P= 0.001 <0.01; Nutren(R): t= 5.2, P= 0.001<0.01). The MTV forwater and Nutren(R) were significantly lower in FD (water: 1014±288 vs 1749±275 mL; t = 7.9, P = 0.001<0.01;Nutren(R): 652±168 vs 1278±286 mL; t= 6.7, P = 0.001<0.01). With the volume tolerated by the controls, the percentile 10 was determined as the lower limit fortolerance. Sensitivity and specificity were 0.90, 0.95 for water and 0.95, 0.95 for Nutren(R) tests.CONCLUSION: A drinking test with water or a nutritional beverage can discriminate between FD patients and healthy subjects in Mexico, with high sensitivity and specificity. These tests could be used as objective, noninvasive, and safe diagnostic approaches for FD patients.
基金This work was financially supported by the National Natural Science Foundation of China (Grant No10602055)Nature Science Foundation of China Jiliang University (Grant No XZ0501)
文摘In this paper, an inner turret moored FPSO which works in the water of 320 m depth, is selected to study the socalled "passively-truncated + numerical-simulation" type of hybrid model testing technique while the tnmcated water depth is 160 m and the model scale ), = 80. During the investigation, the optimization design of the equivalent-depth truncated system is performed by using the similarity of the static characteristics between the truncated system and the full depth one as the objective function. According to the truncated system, the corresponding physical test model is made. By adopting the coupling time domain simulation method, the tnmcated system model test is numerically reconstructed to carefully verify the computer simulation software and to adjust the corresponding hydrodynamic parameters. Based on the above work, the numerical extrapolation to the full depth system is performed by using the verified computer software and the adjusted hydrodyrmmic parameters. The full depth system model test is then performed in the basin and the results are compared with those from the numerical extrapolation. At last, the implementation procedure and the key technique of the hybrid model testing of the deep-sea platforms are summarized and printed. Through the above investigations, some beneficial conclusions are presented.
文摘AIM:To compare the impact of the right recumbent position with the sitting position on gastric emptying of water. METHODS:In eight healthy male volunteers,the 13C acetate breath test was performed twice to assess gastric emptying of 100 mL tap water.Subjects were seated in one test and lying on their right side in the other.In both positions,pulmonary 13CO2 exhalation curves were obtained by plotting breath data against time.Percent gastric retention curves were created by analyzing data using the Wagner-Nelson protocol. RESULTS:No significant posture effect was found in pulmonary 13CO2 output curves(P=0.2150),whereas a significant effect was seen in gastric retention curves (P=0.0315).The percent retention values at 10 min and 15 min were significantly smaller when subjects were in the right recumbent position compared with the seated position(P<0.05).Our results verified the accelerating effect of the right recumbent position on gastric emptying of non-nutritive solutions.Concerning clinical implications,this study suggests that placing patients with acute pain on their right side after oral administration of analgesic drugs in solution is justified as an effective practice for rapid pain relief.For patients with gastrointestinal reflux symptoms,sleeping in the right recumbent position may reduce nocturnal symptoms,as delayed gastric emptying can cause reflux symptoms. CONCLUSION:Gastric emptying of water occurs more quickly when a subject lies on the right side compared with sitting.
基金This paper is supported by the Research Fund for the Doctoral Program of Higher Education of China.
文摘This paper introduces model test results of water pressure in a fault, which is located in a slope and 16 different conditions. The results show that the water pressures in fault can be expressed by a linear function, which is similar to the theoretical model suggested by Hoek. Factors affecting water pressures are water level in tension crack, dip angle of fault, the height of filling materials and thickness of fault zone in sequence.
基金funded by the Key Program of National Natural Science Foundation of China (41630643)the National Key Research and Development Program of China (2017YFC1501302)the Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan) (CUGCJ1701)
文摘Many landslides in reservoir areas continuously deform under cyclic water level fluctuations due to reservoir operations. In this paper,a landslide model, developed for a typical colluvial landslide in the Three Gorges Reservoir area, is used to study the effect of cyclic water level fluctuations on the landslide. Five cyclic water level fluctuations were implemented in the test, and the fluctuation rate in the last two fluctuations doubled over the first three fluctuations. The pore water pressure and lateral landslide profiles were obtained during the test. A measurement of the landslide soil loss was proposed to quantitatively evaluate the influence of water level fluctuations. The test results show that the first water level rising is most negative to the landslide among the five cycles. The fourth drawdown with a higher drawdown rate caused further large landslide deformation. An increase of the water level drawdown rate is much more unfavorable to the landslide than an increase of the water level rising rate. In addition, the landslide was found to have an adaptive ability to resist subsequent water level fluctuations after undergoing large deformation during a water level fluctuation. The landslide deformation and observations in the field were found to support the test results well.
文摘With the rapid economic development and the continuous improvement of peoples living standards, ensuring the safety of water supply has become an urgent task. The national requirements for water quality indicators are becoming more and more stringent, and water quality testing is a process of evaluating water quality. By analyzing the results of water quality testing, water quality can be judged and dealt with accordingly. Starting from the direction of improving the accuracy and stability of water quality testing, this paper focuses on analyzing some of the reasons, and puts forward some suggestions on improving the accuracy and stability of water quality testing.
文摘From the birth of life, water is the source of life, and its quality is closely related to people's daily life. Therefore, water quality testing is particularly important. Therefore, relevant staff must pay attention to water quality testing to ensure that the water quality of drinking water can meet the requirements of relevant standards. In recent years, the application of environmental information technology and big data technology in water quality monitoring has improved the use efficiency of environmental monitoring equipment. The application of intelligent and automatic water quality detection system can realize continuous detection of water quality, and can also quickly detect sudden changes in water quality inside the reservoir, so as to provide more accurate data support for water quality detection, water source protection and environmental protection. Therefore, water quality testing methods should be continuously optimized and adjusted to make them more scientific and perfect, and to provide more accurate drinking water quality testing data for residents.
文摘With the continuous development of China's economy and society, people gradually improve the requirements of water quality, constantly pay attention to the water quality test results, water resources not only meet People's Daily drinking, and social production and life is widely used. Rapid and accurate water quality testing can not only reflect the current situation of the water environment, but also for water environment management and pollution source control and leadership decision-making at all levels to provide an important scientific basis, but also through the water quality testing results for the relevant statistical analysis, control the water quality change law, and then improve the water quality. When people drink substandard water, it will not only cause waste of water resources, but also cause harm to people's health. In order to respond to the sustainable development strategy put forward by the country and improve people's living standards, improving water quality is an inevitable choice, and water quality detection is the prerequisite for improving water quality.
文摘This paper discusses the monitoring section layout, sampling point layout, sampling time and sampling frequency determination, preparation before water sample collection, collection method, collector, industrial sewage collection, flow determination, water sample transportation and the whole process of river water quality control.
文摘Water vapor monitoring system by Beidou satellite is a new detection system in meteorological department, which makes receiving amount of detected data and data storage and transmission pressure increase. Here, we try to use data compression to relieve pressure. Compres- sion software of water vapor monitoring system by Beidou satellite can be designed into three components: real-time compression software, check compression software and manual compression software, which respectively completes the compression tasks under real-time receiving, in-time check and separate compression, thereby forming a perfect compression system. Taking the design of manual compression software as guide,and using c language to develop,compression test of original receiving data is conducted. Test result proves that the system can carry out batch auto- matic compression, and compression rate can reach 30% ,which can reach the target of saving space in a degree.
基金Supported by the National Key Basic Research and Development Program(973 Program),China(2015CB251205)
文摘During deep water oil well testing, the low temperature environment is easy to cause wax precipitation, which affects the normal operation of the test and increases operating costs and risks. Therefore, a numerical method for predicting the wax precipitation region in oil strings was proposed based on the temperature and pressure fields of deep water test string and the wax precipitation calculation model. And the factors affecting the wax precipitation region were analyzed. The results show that: the wax precipitation region decreases with the increase of production rate, and increases with the decrease of geothermal gradient, increase of water depth and drop of water-cut of produced fluid, and increases slightly with the increase of formation pressure. Due to the effect of temperature and pressure fields, wax precipitation region is large in test strings at the beginning of well production. Wax precipitation region gradually increases with the increase of shut-in time. These conclusions can guide wax prevention during the testing of deep water oil well, to ensure the success of the test.