In extended-reach or long-horizontal drilling,cuttings usually deposit at the bottom of the annulus.Once cuttings accumulate to a certain thickness,complex problems such as excessive torque and drag,tubing buckling,an...In extended-reach or long-horizontal drilling,cuttings usually deposit at the bottom of the annulus.Once cuttings accumulate to a certain thickness,complex problems such as excessive torque and drag,tubing buckling,and pipe stuck probably occur,which results in a lot of non-productive time and remedial operations.Cuttings bed remover can efficiently destroy deposited cuttings in time through hydraulic and mechanical stirring effects.This paper aims to build a method for hole cleaning evaluation and installation spacing optimization of cuttings bed remover to improve the wellbore cleaning effect.Firstly,a Computational Fluid Dynamics approach with Eulerian—Eulerian multiphase model was utilized to investigate the mechanism of cuttings transportation,and a new type of cuttings bed remover was designed.Next,an evaluation method of hole cleaning effect of remover was established.After that,the effects of several drilling parameters on hole cleaning including flow rate of drilling fluid,rotational speed of drillpipe,rate of penetration,wellbore size,rheological property of drilling fluid,and remover eccentricity on the performance of cuttings bed remover were investigated.The results demonstrate that the new type of remover with streamline blade performs better than conventional removers.The efficiency of hole cleaning is greatly improved by increasing the rotational speed of drillpipe,flow rate of drilling fluid,remover eccentricity,and 6 rpm Fann dial reading for drilling fluid.While higher rate of penetration and large wellbore size result in worse hole cleaning.These findings can serve as an important guide for the structure optimization design of cuttings bed remover and installation spacing of removers.展开更多
The aim of the study was to identify the relationship between molecular subtypes of breast cancer (BC) and the morphological characteristics of axillary lymph nodes (ALN) and metastatic risk in BC patients to clarify ...The aim of the study was to identify the relationship between molecular subtypes of breast cancer (BC) and the morphological characteristics of axillary lymph nodes (ALN) and metastatic risk in BC patients to clarify danger degree and justification of removal before metastases appear. Material and methods. Tumor molecular subtypes of 116 female BC patients aged 24 - 75 (53.9 ± 0.8) were determined by tumor tissue immunohistological examination (obtained by tru-cut biopsy), and the BC was classified as Luminal A, Luminal B/HER2−, Luminal B/HER2+, TNBC, and HER2+ subtypes. To interpret the results for the BC receptor status, immunohistochemical analysis was performed and interpreted according to the Allred scale. Lymph node size, shape, structure and conglomerates availability were recorded according to ultrasonography (USG) examination evaluated on “LOGIQ C5-Premium” (2012). Blood CA-15-3 levels were analyzed using a COBAS-e 411 automated analyzer. Statistical analysis of the obtained results was carried out using the SPSS-26 software package, and based on the t-Student-Bonferroni and H-Kruskal-Wallis criteria. The sensitivity and specificity of the indicators studied were determined using ROC statistical analysis. Results showed a significant association of some subtypes, as well as receptor expression, with tumor metastasis to ALN. Conclusion: 1) The HER2+ subtype is the most aggressive in terms of ALN metastasis. Although TNBC is the most aggressive subtype in general, it is characterized by fewer metastases to the ALN than the HER2+ subtype. 2) Metastatic ALNs can be distinguished based on their cortical structure before tumor tissue biopsy, which is economically profitable. These LNs can be removed without biopsy.展开更多
In order to solve the problem of limited makeup removal ability of a single surfactant of Peg-20 glyceryl triisostearate in makeup remover,an efficient system was prepared which contained PEG-20 glyceryl triisostearat...In order to solve the problem of limited makeup removal ability of a single surfactant of Peg-20 glyceryl triisostearate in makeup remover,an efficient system was prepared which contained PEG-20 glyceryl triisostearate and a combination of Sorbeth-30 tetraoleate and Peg-5 glyceryl triisostearate.Leather test,skin colorimeter test and consumer self-evaluation were used to assess the makeup removal ability,rinsing performance and softness skin feel of the efficient makeup remover base.The results showed that a 7%combination of Sorbeth-30 tetraoleate and PEG-5 glyceryl triisostearate could significantly improve the comprehensive performance of single PEG-20 glyceryl triisostearate makeup remover system,furthermore,they performed best at the ratio of 6:1.We hope the findings can have guiding significance for the development of makeup remover products.展开更多
Five monolithic catalysts with low noble metal content were prepared by irnmerge method （Pt/γ=Al2O3, Pt/La-Al2O3, Pt/YSZ-AI203, Pt＋Pd/La-Al2O3 and Pd/La-Al2O3） and their activity measurements were carried out in a...Five monolithic catalysts with low noble metal content were prepared by irnmerge method （Pt/γ=Al2O3, Pt/La-Al2O3, Pt/YSZ-AI203, Pt＋Pd/La-Al2O3 and Pd/La-Al2O3） and their activity measurements were carried out in a conventional fixed-bed flow reactor. The results show that La-Al2O3 can promote activity of the prepared catalysts and can decrease the complete conversion temperature of cooking fume. The Pt/La-Al2O3 catalyst has the highest activity and can be applied in wide range of gas hourly space velocity （GHSV）. Some characterizations （XRD, TPR） were carried out with the objective to explain differences in catalytic behaviors. The prepared catalyst showed a great potential for application.展开更多
to study the influence of Chinese medicines for promoting blood circulation to remove blood stasis on fibrinogen(FIB)and D-dimer(DD)in plasma of patients with cerebral thrombosis. Method:73 inpatients with acute cereb...to study the influence of Chinese medicines for promoting blood circulation to remove blood stasis on fibrinogen(FIB)and D-dimer(DD)in plasma of patients with cerebral thrombosis. Method:73 inpatients with acute cerebral thrombosis were randomly divided into a control group of 34 cases and a treatment group of 39 cases.The content of FIB and DD in plasma was detected before treatment and on the 7th and 14th days after treatment.Result:FIB content in plasma after treatment was lower than that before treatment in the control group(P<0.01)and more remarkable in the treatment group(P<0.001).There was an obvious difference in DD content before and after treatment in both groups.DD content on the 7th and 14th days after treatment in the treatment group was obviously higher than that in the control group(P<0.01 and P<0.05 respectively). Conclusion:Chinese medicines for promoting blood circulation to remove blood stasis can reduce the FIB content in plasma of patients with cerebral thrombosis,raise the DD content in plasma, cause the peak of DD content appear earlier and obviously improve hypercoagulability of blood in patients with cerebral thrombosis.展开更多
This paper presents a model derived for quantitative evaluation and prediction of the concentration of phosphorus removed during pyro-hydro beneficiation of iron oxide ore. Potassium hydroxide was used as the leaching...This paper presents a model derived for quantitative evaluation and prediction of the concentration of phosphorus removed during pyro-hydro beneficiation of iron oxide ore. Potassium hydroxide was used as the leaching solution and the reaction vessel containing the solution and ore was heated at a temperature of 600℃ for 10 minutes. The results of the investigation indicates that the model;P = (e0.7827) S predicts the concentration of phosphorus removed, based on the concentration of sulphur simultaneously removed. It was observed that the validity of the model is rooted in the expression lnP = lnN + lnS where both sides of the expression are approximately equal to 4. The maximum deviation of the model-predicted concentration of removed phosphorus from the corresponding concentration obtained from the experiment was less than 3%. The concentrations of phosphorus removed per unit mass-input of iron oxide ore as obtained from experiment and derived model are 0.8917 and 1.0354 mg/kg g-1 respectively. Similarly, the concentrations of phosphorus removed per unit concentration of removed sulphur as obtained from experiment and derived model are 1.8838 and 2.1874 mg/kg (mg/kg)-1 respectively. This implies that the concentration of phosphorus removed is approximately equal to the concentration of simultaneously removed sulphur during the beneficiation process.展开更多
Membrane separation, a new technology for removing VOCs including pervaporation, vapor permeation, membrane contactor, and membrane bioreactor was presented. Comparing with traditional techniques, these special techni...Membrane separation, a new technology for removing VOCs including pervaporation, vapor permeation, membrane contactor, and membrane bioreactor was presented. Comparing with traditional techniques, these special techniques are an efficient and energy saving technology. Vapor permeation can be applied to recovery of organic solvents from exhaust streams. Membrane contactor could be used for removing or recovering VOCs from air or wastewater. Pervaporation and vapor permeation are viable methods for removing VOCs from wastewater to yield a VOC concentrate which could either be destroyed by conventional means, or be recycled for reuse.展开更多
Computer chip is always accompanied by the increase of heat dissipation and miniaturization. The miniature heat pipes are widely used in notebook computer to resolve the heat dissipation problems. Maximum heat removed...Computer chip is always accompanied by the increase of heat dissipation and miniaturization. The miniature heat pipes are widely used in notebook computer to resolve the heat dissipation problems. Maximum heat removed model of miniature heat pipes building by grey model is presented. In order to know the foundation for modeling, the smooth grade of error examination is inquired and the accuracy of grey relational grade is verified. The model can be used to select a suitable heat pipes to solve electric heat problems in the future. Final results show that the grey model only needs four experiment data and its error value is less than 10%, further, it is better than computational fluid dynamics （CFD） model.展开更多
The treatment of hy-pertensive cerebral hemorrhage(HCH)by activatingblood circulation to removestasis(ABCRS)is a newtherapeutic approach,which is initiated by clinical specialists of TCM andintegrative Chinese andwest...The treatment of hy-pertensive cerebral hemorrhage(HCH)by activatingblood circulation to removestasis(ABCRS)is a newtherapeutic approach,which is initiated by clinical specialists of TCM andintegrative Chinese andwestern medicine.Al-though it is not a flawless展开更多
The haze defects on p-type (111) silicon wafers were investigated by means of chemical etching, Fouriertransform infra-red microscopy (FTIR), spreading resistance measurement. secondary ion mass spectroscopy(SLMS), tr...The haze defects on p-type (111) silicon wafers were investigated by means of chemical etching, Fouriertransform infra-red microscopy (FTIR), spreading resistance measurement. secondary ion mass spectroscopy(SLMS), transmission electron microscopy (TEM) equipped with an energy-dispersive X-ray spectrometer(EDX). The haze defects are the precipitates of silicide of metal impurities (Fe, Ni) on the wafer surface.The formation of haze defects can efficiently be inhibited by utilizing the technology of fast neutronirradiation combined with the internal gettering (IG), and then, the formation and removement mechanismof the haze defects have been discussed in this paper.展开更多
Firstly, physical and chemical properties of dust removed from BOF gas are analyzed, and then the cold banding technology of dust removed from BOF gas and its application are introduced. Tests have proved that using c...Firstly, physical and chemical properties of dust removed from BOF gas are analyzed, and then the cold banding technology of dust removed from BOF gas and its application are introduced. Tests have proved that using cooled agglomerated pellets made of the dust removed from BOF gas and small amounts of modified starch as a coolant and slagging agent in steel production can bring about considerable economic, social and environmental benefits.展开更多
Africa is a continent with many development challenges. Poverty, inadequate healthcare and educa-tional deficits are all obstacles to its development. However, Africa is also a continent that has confidence in its abi...Africa is a continent with many development challenges. Poverty, inadequate healthcare and educa-tional deficits are all obstacles to its development. However, Africa is also a continent that has confidence in its ability to realize its full development potential, be it economic, cultural or political.展开更多
Cuttings accumulation in horizontal drilling of a shale gas well is one of the main reasons for high drilling torque and drag and serious backing pressure and consequently influencing the rate of penetration(ROP),so i...Cuttings accumulation in horizontal drilling of a shale gas well is one of the main reasons for high drilling torque and drag and serious backing pressure and consequently influencing the rate of penetration(ROP),so inhibiting the generation of a cuttings bed and keeping the hole clean is an important prerequisite to ensure the smooth and safe drilling of horizontal section.In order to improve the hole cleaning efficiency of horizontal sections,this paper studied the decay laws of helical flow induced by helix angles and rotation speed of a newly developed cuttings bed remover with V-shaped blades for horizontal wells and their influences on the resuspension distribution of cuttings particles by virtue of the CFD numerical simulation method and EulereEuler binary-fluid model,combined with the theory of particle dynamics.Then,the parameters such as blade rotation speed and blade helix angle were optimized.And the following research results were obtained.First,with the increase of the rotation speed,cuttings deposit at the bottom of the annulus deflects to a certain degree.And the higher the rotation speed,the more obvious the deflection.Second,annulus pressure drop loss increases with the increase of the helix angle.And this phenomenon is more obvious when the helix angle is larger.Third,the field test results in Well Changning H25-7 of the southern Sichuan Basin show that after the application of the newly developed cuttings bed remover for horizontal wells,the drilling friction is decreased by 33%,the tripping is smooth without sticking.And in the process of its application,no complex downhole accident happened.Obviously,it provides good hole cleaning to ensure the safe and smooth implementation of the later casing running operation.In conclusion,this newly developed cuttings bed remover can satisfy the demand of cutting bed cleaning and drilling cost reduction and efficiency improvement of horizontal wells,so it is worth popularizing and applying.What's more,it provides guidance and reference for the design of similar cuttings bed removers.展开更多
One year has passed since the revised Law on the Protection of the Rights and Interests of Consumers came into effect on March 15, 2014, the World Consumer Rights Day. Following the changes, consumers can return goods...One year has passed since the revised Law on the Protection of the Rights and Interests of Consumers came into effect on March 15, 2014, the World Consumer Rights Day. Following the changes, consumers can return goods they are dissatisfied with and get an unconditional refund within seven days of purchase. This applies to not only Internet shopping but also TV- and telephone-based sales.展开更多
A novel flux charging method and a crucible quenching method were employed to study the mechanism of solid fluxes refining method regarding the removal of oxide inclusions(Al_2O_3) from molten aluminum. Electrochemica...A novel flux charging method and a crucible quenching method were employed to study the mechanism of solid fluxes refining method regarding the removal of oxide inclusions(Al_2O_3) from molten aluminum. Electrochemical polishing method was adopted to prepare surfaces of the samples. Through experiments, the morphology of the residual solidified flux in the solidified samples as well as the wetting action of the molten flux during refining were observed for the first time. Three wetting regimes denoted by absorbing regime, engulfing regime and penetration regime correlating with the removal of oxide films(the most typical and common oxide inclusions in molten aluminum) were proposed in terms of different types and distributions of oxide films and different size ratios of the molten flux to oxide films. Particularly, from a thermodynamic point of view, for the first time, the penetration regime provided concrete evidence that the practical oxide inclusions can be wet by molten flux under ambient fluid of molten aluminum. A spreading model was proposed, according to which ingredients and size parameters of practical solid fluxes can be optimized.展开更多
基金the financial support from the Natural Science Foundation of China(Grant Nos.52222401,52234002,52394250,52394255)Science Foundation of China University of Petroleum,Beijing(Grant No.ZXZX20230083)other projects(ZLZX2020-01-07-01)。
文摘In extended-reach or long-horizontal drilling,cuttings usually deposit at the bottom of the annulus.Once cuttings accumulate to a certain thickness,complex problems such as excessive torque and drag,tubing buckling,and pipe stuck probably occur,which results in a lot of non-productive time and remedial operations.Cuttings bed remover can efficiently destroy deposited cuttings in time through hydraulic and mechanical stirring effects.This paper aims to build a method for hole cleaning evaluation and installation spacing optimization of cuttings bed remover to improve the wellbore cleaning effect.Firstly,a Computational Fluid Dynamics approach with Eulerian—Eulerian multiphase model was utilized to investigate the mechanism of cuttings transportation,and a new type of cuttings bed remover was designed.Next,an evaluation method of hole cleaning effect of remover was established.After that,the effects of several drilling parameters on hole cleaning including flow rate of drilling fluid,rotational speed of drillpipe,rate of penetration,wellbore size,rheological property of drilling fluid,and remover eccentricity on the performance of cuttings bed remover were investigated.The results demonstrate that the new type of remover with streamline blade performs better than conventional removers.The efficiency of hole cleaning is greatly improved by increasing the rotational speed of drillpipe,flow rate of drilling fluid,remover eccentricity,and 6 rpm Fann dial reading for drilling fluid.While higher rate of penetration and large wellbore size result in worse hole cleaning.These findings can serve as an important guide for the structure optimization design of cuttings bed remover and installation spacing of removers.
文摘The aim of the study was to identify the relationship between molecular subtypes of breast cancer (BC) and the morphological characteristics of axillary lymph nodes (ALN) and metastatic risk in BC patients to clarify danger degree and justification of removal before metastases appear. Material and methods. Tumor molecular subtypes of 116 female BC patients aged 24 - 75 (53.9 ± 0.8) were determined by tumor tissue immunohistological examination (obtained by tru-cut biopsy), and the BC was classified as Luminal A, Luminal B/HER2−, Luminal B/HER2+, TNBC, and HER2+ subtypes. To interpret the results for the BC receptor status, immunohistochemical analysis was performed and interpreted according to the Allred scale. Lymph node size, shape, structure and conglomerates availability were recorded according to ultrasonography (USG) examination evaluated on “LOGIQ C5-Premium” (2012). Blood CA-15-3 levels were analyzed using a COBAS-e 411 automated analyzer. Statistical analysis of the obtained results was carried out using the SPSS-26 software package, and based on the t-Student-Bonferroni and H-Kruskal-Wallis criteria. The sensitivity and specificity of the indicators studied were determined using ROC statistical analysis. Results showed a significant association of some subtypes, as well as receptor expression, with tumor metastasis to ALN. Conclusion: 1) The HER2+ subtype is the most aggressive in terms of ALN metastasis. Although TNBC is the most aggressive subtype in general, it is characterized by fewer metastases to the ALN than the HER2+ subtype. 2) Metastatic ALNs can be distinguished based on their cortical structure before tumor tissue biopsy, which is economically profitable. These LNs can be removed without biopsy.
文摘In order to solve the problem of limited makeup removal ability of a single surfactant of Peg-20 glyceryl triisostearate in makeup remover,an efficient system was prepared which contained PEG-20 glyceryl triisostearate and a combination of Sorbeth-30 tetraoleate and Peg-5 glyceryl triisostearate.Leather test,skin colorimeter test and consumer self-evaluation were used to assess the makeup removal ability,rinsing performance and softness skin feel of the efficient makeup remover base.The results showed that a 7%combination of Sorbeth-30 tetraoleate and PEG-5 glyceryl triisostearate could significantly improve the comprehensive performance of single PEG-20 glyceryl triisostearate makeup remover system,furthermore,they performed best at the ratio of 6:1.We hope the findings can have guiding significance for the development of makeup remover products.
基金Project supported by the National Basic Research Program of China(No.G1999022407).
文摘Five monolithic catalysts with low noble metal content were prepared by irnmerge method （Pt/γ=Al2O3, Pt/La-Al2O3, Pt/YSZ-AI203, Pt＋Pd/La-Al2O3 and Pd/La-Al2O3） and their activity measurements were carried out in a conventional fixed-bed flow reactor. The results show that La-Al2O3 can promote activity of the prepared catalysts and can decrease the complete conversion temperature of cooking fume. The Pt/La-Al2O3 catalyst has the highest activity and can be applied in wide range of gas hourly space velocity （GHSV）. Some characterizations （XRD, TPR） were carried out with the objective to explain differences in catalytic behaviors. The prepared catalyst showed a great potential for application.
文摘to study the influence of Chinese medicines for promoting blood circulation to remove blood stasis on fibrinogen(FIB)and D-dimer(DD)in plasma of patients with cerebral thrombosis. Method:73 inpatients with acute cerebral thrombosis were randomly divided into a control group of 34 cases and a treatment group of 39 cases.The content of FIB and DD in plasma was detected before treatment and on the 7th and 14th days after treatment.Result:FIB content in plasma after treatment was lower than that before treatment in the control group(P<0.01)and more remarkable in the treatment group(P<0.001).There was an obvious difference in DD content before and after treatment in both groups.DD content on the 7th and 14th days after treatment in the treatment group was obviously higher than that in the control group(P<0.01 and P<0.05 respectively). Conclusion:Chinese medicines for promoting blood circulation to remove blood stasis can reduce the FIB content in plasma of patients with cerebral thrombosis,raise the DD content in plasma, cause the peak of DD content appear earlier and obviously improve hypercoagulability of blood in patients with cerebral thrombosis.
文摘This paper presents a model derived for quantitative evaluation and prediction of the concentration of phosphorus removed during pyro-hydro beneficiation of iron oxide ore. Potassium hydroxide was used as the leaching solution and the reaction vessel containing the solution and ore was heated at a temperature of 600℃ for 10 minutes. The results of the investigation indicates that the model;P = (e0.7827) S predicts the concentration of phosphorus removed, based on the concentration of sulphur simultaneously removed. It was observed that the validity of the model is rooted in the expression lnP = lnN + lnS where both sides of the expression are approximately equal to 4. The maximum deviation of the model-predicted concentration of removed phosphorus from the corresponding concentration obtained from the experiment was less than 3%. The concentrations of phosphorus removed per unit mass-input of iron oxide ore as obtained from experiment and derived model are 0.8917 and 1.0354 mg/kg g-1 respectively. Similarly, the concentrations of phosphorus removed per unit concentration of removed sulphur as obtained from experiment and derived model are 1.8838 and 2.1874 mg/kg (mg/kg)-1 respectively. This implies that the concentration of phosphorus removed is approximately equal to the concentration of simultaneously removed sulphur during the beneficiation process.
基金TheNationalNaturalScienceFoundationofChina (No .2 9836 16 0 )
文摘Membrane separation, a new technology for removing VOCs including pervaporation, vapor permeation, membrane contactor, and membrane bioreactor was presented. Comparing with traditional techniques, these special techniques are an efficient and energy saving technology. Vapor permeation can be applied to recovery of organic solvents from exhaust streams. Membrane contactor could be used for removing or recovering VOCs from air or wastewater. Pervaporation and vapor permeation are viable methods for removing VOCs from wastewater to yield a VOC concentrate which could either be destroyed by conventional means, or be recycled for reuse.
文摘Computer chip is always accompanied by the increase of heat dissipation and miniaturization. The miniature heat pipes are widely used in notebook computer to resolve the heat dissipation problems. Maximum heat removed model of miniature heat pipes building by grey model is presented. In order to know the foundation for modeling, the smooth grade of error examination is inquired and the accuracy of grey relational grade is verified. The model can be used to select a suitable heat pipes to solve electric heat problems in the future. Final results show that the grey model only needs four experiment data and its error value is less than 10%, further, it is better than computational fluid dynamics （CFD） model.
文摘The treatment of hy-pertensive cerebral hemorrhage(HCH)by activatingblood circulation to removestasis(ABCRS)is a newtherapeutic approach,which is initiated by clinical specialists of TCM andintegrative Chinese andwestern medicine.Al-though it is not a flawless
文摘The haze defects on p-type (111) silicon wafers were investigated by means of chemical etching, Fouriertransform infra-red microscopy (FTIR), spreading resistance measurement. secondary ion mass spectroscopy(SLMS), transmission electron microscopy (TEM) equipped with an energy-dispersive X-ray spectrometer(EDX). The haze defects are the precipitates of silicide of metal impurities (Fe, Ni) on the wafer surface.The formation of haze defects can efficiently be inhibited by utilizing the technology of fast neutronirradiation combined with the internal gettering (IG), and then, the formation and removement mechanismof the haze defects have been discussed in this paper.
文摘Firstly, physical and chemical properties of dust removed from BOF gas are analyzed, and then the cold banding technology of dust removed from BOF gas and its application are introduced. Tests have proved that using cooled agglomerated pellets made of the dust removed from BOF gas and small amounts of modified starch as a coolant and slagging agent in steel production can bring about considerable economic, social and environmental benefits.
文摘Africa is a continent with many development challenges. Poverty, inadequate healthcare and educa-tional deficits are all obstacles to its development. However, Africa is also a continent that has confidence in its ability to realize its full development potential, be it economic, cultural or political.
基金Project supported by the National Major Science and Technology Project“Research and application of key technologies for factory-like well drilling”(No.:2016ZX05022-001)the National Major Science and Technology Project“Test and application of 3-D optimized and fast drilling technology for cluster horizontal well in shale gas reservoirs”(No.:2016ZX05062003)CNPC Major Scientific Research and Technical Development Project“Integration and demonstration of drilling speed/efficiency improvement technologies for deep well and horizontal well”(No.:2018E-2108)。
文摘Cuttings accumulation in horizontal drilling of a shale gas well is one of the main reasons for high drilling torque and drag and serious backing pressure and consequently influencing the rate of penetration(ROP),so inhibiting the generation of a cuttings bed and keeping the hole clean is an important prerequisite to ensure the smooth and safe drilling of horizontal section.In order to improve the hole cleaning efficiency of horizontal sections,this paper studied the decay laws of helical flow induced by helix angles and rotation speed of a newly developed cuttings bed remover with V-shaped blades for horizontal wells and their influences on the resuspension distribution of cuttings particles by virtue of the CFD numerical simulation method and EulereEuler binary-fluid model,combined with the theory of particle dynamics.Then,the parameters such as blade rotation speed and blade helix angle were optimized.And the following research results were obtained.First,with the increase of the rotation speed,cuttings deposit at the bottom of the annulus deflects to a certain degree.And the higher the rotation speed,the more obvious the deflection.Second,annulus pressure drop loss increases with the increase of the helix angle.And this phenomenon is more obvious when the helix angle is larger.Third,the field test results in Well Changning H25-7 of the southern Sichuan Basin show that after the application of the newly developed cuttings bed remover for horizontal wells,the drilling friction is decreased by 33%,the tripping is smooth without sticking.And in the process of its application,no complex downhole accident happened.Obviously,it provides good hole cleaning to ensure the safe and smooth implementation of the later casing running operation.In conclusion,this newly developed cuttings bed remover can satisfy the demand of cutting bed cleaning and drilling cost reduction and efficiency improvement of horizontal wells,so it is worth popularizing and applying.What's more,it provides guidance and reference for the design of similar cuttings bed removers.
文摘One year has passed since the revised Law on the Protection of the Rights and Interests of Consumers came into effect on March 15, 2014, the World Consumer Rights Day. Following the changes, consumers can return goods they are dissatisfied with and get an unconditional refund within seven days of purchase. This applies to not only Internet shopping but also TV- and telephone-based sales.
基金financially supported by the International Science&Technology Cooperation Program of China(No.2015DFR50470)Guangdong Provincial Science&Technology Foundation(No.2015B090926013)
文摘A novel flux charging method and a crucible quenching method were employed to study the mechanism of solid fluxes refining method regarding the removal of oxide inclusions(Al_2O_3) from molten aluminum. Electrochemical polishing method was adopted to prepare surfaces of the samples. Through experiments, the morphology of the residual solidified flux in the solidified samples as well as the wetting action of the molten flux during refining were observed for the first time. Three wetting regimes denoted by absorbing regime, engulfing regime and penetration regime correlating with the removal of oxide films(the most typical and common oxide inclusions in molten aluminum) were proposed in terms of different types and distributions of oxide films and different size ratios of the molten flux to oxide films. Particularly, from a thermodynamic point of view, for the first time, the penetration regime provided concrete evidence that the practical oxide inclusions can be wet by molten flux under ambient fluid of molten aluminum. A spreading model was proposed, according to which ingredients and size parameters of practical solid fluxes can be optimized.
