Preparation and performance evaluation of the slickwater using novel polymeric drag reducing agent with high temperature and shear resistance ability

Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performance is severely affected at high temperatures.Drag reducing agent is the key to determine the drag reducing performance of slickwater.In this work,in order to further improve the temperature resistance of slickwater,a temperature-resistant polymeric drag reducing agent(PDRA)was synthesized and used as the basis for preparing the temperature-resistant slickwater.The slickwater system was prepared with the compositions of 0.2 wt%PDRA,0.05 wt%drainage aid nonylphenol polyoxyethylene ether phosphate(NPEP)and 0.5 wt%anti-expansion agent polyepichlorohydrindimethylamine(PDM).The drag reduction ability,rheology properties,temperature and shear resistance ability,and core damage property of slickwater were systematically studied and evaluated.In contrast to on-site drag reducing agent(DRA)and HPAM,the temperature-resistant slickwater demonstrates enhanced drag reduction efficacy at 90℃,exhibiting superior temperature and shear resistance ability.Notably,the drag reduction retention rate for the slickwater achieved an impressive 90.52%after a 30-min shearing period.Additionally,the core damage is only 5.53%.We expect that this study can broaden the application of slickwater in high-temperature reservoirs and provide a theoretical basis for field applications.

Effect of Shrinkage Reducing Agent and Steel Fiber on the Fluidity and Cracking Performance of Ultra-High Performance Concrete

Due to the low water-cement ratio of ultra-high-performance concrete(UHPC),fluidity and shrinkage cracking are key aspects determining the performance and durability of this type of concrete.In this study,the effects of different types of cementitious materials,chemical shrinkage-reducing agents(SRA)and steel fiber(SF)were assessed.Compared with M2-UHPC and M3-UHPC,M1-UHPC was found to have better fluidity and shrinkage cracking performance.Moreover,different SRA incorporation methods,dosage and different SF types and aspect ratios were implemented.The incorporation of SRA and SF led to a decrease in the fluidity of UHPC.SRA internal content of 1%(NSRA-1%),SRA external content of 1%(WSRA-1%),STS-0.22 and STE-0.7 decreased the fluidity of UHPC by 3.3%,8.3%,9.2%and 25%,respectively.However,SRA and SF improved the UHPC shrinkage cracking performance.NSRA-1%and STE-0.7 reduced the shrinkage value of UHPC by 40%and 60%,respectively,and increased the crack resistance by 338%and 175%,respectively.In addition,the addition of SF was observed to make the microstructure of UHPC more compact,and the compressive strength and flexural strength of 28 d were increased by 26.9%and 19.9%,respectively.

Effects of Plant Growth Regulators on the Contents of Reducing Sugar and Starch in Potato(Solanum tuberosum L.)

[Objective] The aim was to investigate the effects of plant growth regulators on contents of reducing sugar and starch in potato（Solanum tuberosum L.）.[Method]A potato cultivar named ＇Holand-212＇ with three treatments by spraying Diethyl aminoethyl hexanoate（DTA-6）,Uniconazole（S3307）and SOD mimics（SODM）were employed to compare differences of the contents of reducing sugar and starch in potato leaves,stolons and tubers in a field experiment.[Result]DTA-6 treatment could significantly reduce the contents of starch and reducing sugar in potato stolons in the period of 100-110 d after seeding,and it could also reduce the content of reducing sugar in tubers,but there is an opposite result in leaves in the same period,significantly.S3307 could extremely significantly increase the content of starch,and can promote the transfer of starch in stolons,in addition,it also could reduce the content of reducing sugar in tubers,and extremely significantly increase the content of starch in leaves at the 110 d after sowing.Moreover,there is a similar effect between SODM and S3307.[Conclusion]The research results are significant for understanding mechanisms of plant growth regulators and promoting application of plant growth regulator in potato.

面向多源异构的电力工程数据融合处理技术研究

随着电力工程中自动化、信息化设备的日益增多,对电力工程数据的分析与处理能力有了更高的要求。针对这一问题,文中开展了面向多源异构的电力工程数据融合处理技术研究。通过预先设计好的数据框架进行关联操作,实现数据监测与处理分析。为了提高整体数据与局部数据之间的协调性,对融合数据进行边缘自适应增强处理,结合电力工程定值数据处理方法将样本数据分解为多个子数据集,利用神经网络模型分类融合,采用Reduce机制对融合后的数据进行合并处理,输出结果,从而提高数据融合的效率。以某地区电力工程数据集为样本进行的分析结果表明,所提方法在处理数据时具有更高的效率,产生的绝对误差仅为1.675%,且更适用于大容量数据的场景。

Large-for-size syndrome prophylaxis in infant liver recipients with low body mass

Transplantation of the left lateral section(LLS)of the liver is now an established practice for treating advanced diffuse and unresectable focal liver diseases in children,with variants of the LLS primarily used in infants.However,the surgical challenge of matching the size of an adult donor's graft to the volume of a child's abdomen remains significant.This review explores historical developments,various approaches to measuring the required functional liver mass,and techniques to prevent complications associated with large-for-size grafts in infants.

Capping effect of reducing agents and surfactants in synthesizing silver nanoplates

The effect of reducing agents and surfactants on controlling the silver nanoplates was studied. Two reducing agents, trisodium citrate dehydrate (TSC) and potassium tartrate, were used to reduce the AgNO3 solution. In this redox system, polyvinylpyrrolidone (PVP), sodium dodecyl sulfate (SDS) and arabic gum were served as surfactants. The results showed that reducing agents and surfactants both act as the capping agent adhering to the certain facets of silver seeds to block this surface to grow. The relative intensity of reducing agents also takes an active part in influencing the growth rate and direction of silver seeds. It was also found that halides can accelerate the speed of Ostwald ripening by adding Cl?, Br? and I?into the aqueous and have some effects on the morphology of the nanoplates.

Challenging and Reducing Cultural Stereotypes

Anyplace where differences are found leaves room for stereotypes.Each of us hears or makes stereotypical comments every day,and although sometimes it is necessary to make stereotypes in foreign language teaching and learning,we should always be aware of the negative effects of stereotyping people from other cultures when we use them to interpret behavior.This paper defines stereotypes,discusses how they impede communication and then focuses on some ways to challenge and reduce stereotypes in cross-cultural communication.

Review on the applications and developments of drag reducing polymer in turbulent pipe flow

Drag reduction phenomenon in pipelines has received lots of attention during the past decades due to its potential engineering applications, especially in fluid transporting industries. Various methods to enhance drag reduction have been developed throughout the years and divided into two categories;non-additives method and additives method. Both categories have different types of methods, with different formulations and applications which will generally be discussed in this review. Among all the methods discussed, drag reduction using polymer additive is as one of the most enticing and desirable methods. It has been the subject of research in this field and has been studied extensively for quite some time. It is due to its ability to reduce drag up to 80% when added in minute concentrations. Reducing drag in the pipe will require less pumping power thus offering economic relieves to the industries. So, this paper will be focusing more on the use of polymer additives as drag reducing agent, the general formulations of the additives, major issues involving the use of drag reducing polymers, and the potential applications of it. However, despite the extensive works of drag reduction polymer, there are still no models that accurately explain the mechanism of drag reduction. More studies needed to be done to have a better understanding of the phenomenon. Therefore, future research areas and potential approaches are proposed for future work.

Isolation of Cr(Ⅵ) reducing bacteria from industrial effuents and their potential use in bioremediation of chromium containing wastewater

The present study was aimed to assess the ability of Bacillus sp.JDM-2-1 and Staphylococcus capitis to reduce hexavalent chromium into its trivalent form.Bacillus sp.JDM-2-1 could tolerate Cr（Ⅵ）（4800 μg/mL） and S.capitis could tolerate Cr（Ⅵ）（2800 μg/mL）.Both organisms were able to resist Cd^2＋（50 μg/mL）,Cu^2＋（200 μg/mL）,Pb^2＋（800 μg/mL）,Hg^2＋（50 μg/mL） and Ni2＋（4000 μg/mL）.S.capitis resisted Zn^2＋ at 700 μg/mL while Bacillus sp.JDM-2-1 only showed resistance up to 50 μg/mL.Bacillus sp.JDM-2-1 and S.capitis showed optimum growth at pH 6 and 7,respectively,while both bacteria showed optimum growth at 37°C.Bacillus sp.JDM-2-1 and S.capitis could reduce 85% and 81% of hexavalent chromium from the medium after 96 h and were also capable of reducing hexavalent chromium 86% and 89%,respectively,from the industrial effuents after 144 h.Cell free extracts of Bacillus sp.JDM-2-1 and S.capitis showed reduction of 83% and 70% at concentration of 10 μg Cr（Ⅵ）/mL,respectively.The presence of an induced protein having molecular weight around 25 kDa in the presence of chromium points out a possible role of this protein in chromium reduction.The bacterial isolates can be exploited for the bioremediation of hexavalent chromium containing wastes,since they seem to have a potential to reduce the toxic hexavalent form to its nontoxic trivalent form.

Characterization and technology of fast reducing roasting for fine iron materials

The features of the techniques of fast reducing roasting （FRR） and conventional magnetic roasting, as well as tremendous demands of iron ores in iron and steel industry of China, were briefly described. The test equipment suitable for FRR of fine-grained materials was introduced. Weakly magnetic materials with grain size of 〈0.30 mm were converted into strongly magnetic materials by FRR for several to dozens of seconds. In a weakly reducing atmosphere and at 740-800 ~C, refractory powder iron material （〈0.30 mm） which is rich in specularite, limonite and Mg-Mn siderite was subjected to FRR for a few seconds to 60 s. Concentrate with iron grade of 55.67%-55.21%, high contents of Mg and Mn in the ore is obtained and the yield of magnetic separation reaches 81.66%-86.57%. The results of X-ray diffraction （XRD） analysis and magnetism detection of the material before and after FRR indicate that weakly magnetic material is mainly converted into strongly magnetic material Fe304 with specific saturation magnetic moment. The efficiency of FRR is consistent with TFe recovery of magnetic separation; meantime, the specific sa^u＇ation magnetic moment increases from 33 to 42 times after FRR. Calculations show that speeds of flash magnetic roasting are obtained from several dozen to two or three hundred times, compared with rotary kiln or shaft furnace. This indicates that it is practicable to use the fast reducing roasting technique to improve the comprehensive utilization of iron ore resources.

Study on evaluation of cities' ability reducing earthquake disasters

Cities ability reducing earthquake disasters is a complex system involving numerous factors, moreover the re-search on evaluating cities ability reducing earthquake disasters relates to multi-subject, such as earthquake sci-ence, social science, economical science and so on. In this paper, firstly, the conception of cities ability reducing earthquake disasters is presented, and the ability could be evaluated with three basic elements the possible seis-mic casualty and economic loss during the future earthquakes that are likely to occur in the city and its surround-ings and time required for recovery after earthquake; based upon these three basic elements, a framework, which consists of six main components, for evaluating citys ability reducing earthquake disasters is proposed; then the statistical relations between the index system and the ratio of seismic casualty, the ratio of economic loss and re-covery time are gained utilizing the cities prediction results of earthquake disasters which were made during the ninth five-year plan; at last, the method defining the comprehensive index of cities ability reducing earthquake disasters is presented. Thus the relatively comprehensive theory frame is set up. The frame can evaluate cities ability reducing earthquake disasters absolutely and quantitatively and consequently instruct the decision-making on reducing cities earthquake disasters loss.

SURFACE ANALYSIS OF ALUMINUM ALLOYS INFLUENCED BY SULFATE- REDUCING BACTERIA

The morphology and chemical compositions of surface and corrosion phases for two aluminum alloys(7075 and 2024 ) in the aqueous mediums containing sulfate reducing bacteria(SRB) were studied by the methods of scanning electron microscopy (SEM) and energy dispersive x ray analysis (EDXA). The results showed that serious pitting corrosion took place when aluminum alloys were exposed in the mediums containing SRB, whereas no pitting corrosion were found on the surfaces of aluminum alloys only exposed in blank mediums non containing SRB. It was demonstrated with EDXA that corrosion of aluminum alloys exposed in the solutions containing SRB, whereas the corrosion in the solution non containing microorganisms was attributed to the presence of chloride ions(Cl ).

Role of Removing Stasis and Reducing Heat Formula in Clearance of Proximal Ureteral Calculi after Ureteroscopic Ho:YAG Laser Lithotripsy: A Prospective Randomized Study

Objective To prospectively evaluate the efficacy of Removing Stasis and Reducing Heat Formula in accelerating calculus clearance and improving lower urinary tract symptoms of patients with proximal ureteral calculi after ureteroscopic Ho:YAG laser lithotripsy. Methods A total of 138 patients with proximal ureteral calculi underwent ureteroscopic Ho:YAG laser lithotripsy by a single endocrinologist. Stone size varied from 10 to 15 mm. After operation, the patients were randomly divided into three groups: the control group(group A), tamsulosin group(group B), and Removing Stasis and Reducing Heat Formula group(group C). The treatment lasted for 4 weeks or until stone clearance. The primary and secondary outcomes of the three groups at follow-up were assessed. Results Of the 131 patients available for follow-up, 44 cases were in the group A, 45 in the group B, and 42 in the group C, respectively. The stone free rate at 2 weeks in the groups B and C were significantly higher than that in the group A(95.56%, 97.62% vs. 79.55%; all P<0.05). The ureteral colic rate and mean time of fragment expulsion were significantly reduced in the groups B(4.44% and 7.86±4.99 days) and C(2.43% and 6.76±4.37 days) compared with the group A(22.73% and 11.54±9.89 days, all P<0.05). On the day of double-J ureteric stent removal, the group C differed significantly from the group A in the total International Prostate Symptom Score, irritative subscore, obstructive subscore, and quality of life score(all P<0.05). Conclusion Removing Stasis and Reducing Heat Formula in the medical expulsive therapy might be an effective modality for patients with calculus in the proximal uretera after ureteroscopic Ho:YAG laser lithotripsy.

Aromatic compound degradation by iron reducing bacteria isolated from irrigated tropical paddy soils

Forty-six candidate phenol/benzoate degrading-iron reducing bacteria were isolated from long term irrigated tropical paddy soils by enrichment procedures.Pure cultures and some prepared mixed cultures were examined for ferric oxide reduction and phenol/benzoate degradation.All the isolates were iron reducers,but only 56.5%could couple iron reduction to phenol and/or benzoate degradation,as evidenced by depletion of phenol and benzoate after one week incubation.Analysis of degradative capability using Biolog...

Reducing risk of transjugular intrahepatic portosystemic shunt using ultrasound guided single needle pass

Delayed liver laceration following transjugular intrahepatic portosystemic shunt (TIPS) is a serious and likely underdiagnosed complication. It is however an important complication following TIPS, which remains one of the most technically challenging interventional procedures performed. In addition to laceration, a number of complications regarding bleeding and perforation are well described following TIPS procedures. We feel the adoption of techniques such as ours and that of other authors described in the literature using an ultrasoundguided percutaneous transhepatic approach with a small caliber needle provides a safer and less traumatic procedure and should reduce complications of bleeding and almost completely eliminate the risk of liver laceration. Our procedure was successfully performed under conscious sedation rather than general anaesthesia further reducing the overall procedural risk to the patient.

Acupuncture with reinforcing and reducing twirling manipulation inhibits hippocampal neuronal apoptosis in spontaneously hypertensive rats

To observe the effects of different acupuncture manipulations on blood pressure and target organ damage in spontaneously hypertensive rats（SHRs）, this study used the reinforcing twirling method（1.5–2-mm depth; rotating needle clockwise for 360° and then counter clockwise for 360°, with the thumb moving heavily forward and gently backward, 60 times per minute for 1 minute, and retaining needle for 9 minutes）, the reducing twirling method（1.5–2-mm depth; rotating needle counter clockwise for 360° and then clockwise for 360°, with the thumb moving heavily backward and gently forward, 60 times per minute for 1 minute, and retaining needle for 9 minutes）, and the needle retaining method（1.5–2-mm depth and retaining the needle for 10 minutes）. Bilateral Taichong（LR3） was treated by acupuncture using different manipulations and manual stimulation. Reinforcing twirling, reducing twirling, and needle retaining resulted in a decreased number of apoptotic cells, reduced Bax m RNA and protein expression, and an increased Bcl-2/Bax ratio in the hippocampus compared with the SHR group. Among these groups, the Bcl-2/Bax protein ratio was highest in the reducing twirling group, and the Bcl-2/Bax m RNA ratio was highest in the needle retaining group. These results suggest that reinforcing twirling, reducing twirling, and needle retaining methods all improve blood pressure and prevent target organ damage by increasing the hippocampal Bcl-2/Bax ratio and inhibiting cell apoptosis in the hippocampus in SHR.

Relay-intercropping soybean with maize maintains soil fertility and increases nitrogen recovery efficiency by reducing nitrogen input

Optimized nitrogen(N)management can increase N-use efficiency in intercropping systems.Legume-nonlegume intercropping systems can reduce N input by exploiting biological N fixation by legumes.Measurement of N utilization can help in dissecting the mechanisms underlying N uptake and utilization in legume-nonlegume intercropping systems.An experiment was performed with three planting patterns:monoculture maize(MM),monoculture soybean(SS),and maize-soybean relay intercropping(IMS),and three N application levels:zero N(NN),reduced N(RN),and conventional N(CN)to investigate crop N uptake and utilization characteristics.N recovery efficiency and 15N recovery rate of crops were higher under RN than under CN,and those under RN were higher under intercropping than under the corresponding monocultures.Compared with MM,IMS showed a lower soil N-dependent rate(SNDR)in 2012.However,the SNDR of MM rapidly declined from 86.8%in 2012 to 49.4%in 2014,whereas that of IMS declined slowly from 75.4%in 2012 to 69.4%in 2014.The interspecific N competition rate(NCRms)was higher under RN than under CN,and increased yearly.Soybean nodule dry weight and nitrogenase activities were respectively 34.2%and 12.5%higher under intercropping than in monoculture at the beginning seed stage.The amount(Ndfa)and ratio(%Ndfa)of soybean N2 fixation were significantly greater under IS than under SS.In conclusion,N fertilizer was more efficiently used under RN than under CN;in particular,the relay intercropping system promoted N fertilizer utilization in comparison with the corresponding monocultures.An intercropping system helps to maintain soil fertility because interspecific N competition promotes biological N fixation by soybean by reducing N input.Thus,a maize-soybean relay intercropping system with reduced N application is sustainable and environmentally friendly.

Behavior of raft on settlement reducing piles:Experimental model study

An experimental program is conducted on model piled rafts in sand soil.The experimental program is aimed to investigate the behavior of raft on settlement reducing piles.The testing program includes tests on models of single pile,unpiled rafts and rafts on 1,4,9,or 16 piles.The model piles beneath the rafts are closed ended displacement piles installed by driving.Three lengths of piles are used in the experiments to represent slenderness ratio,L/D,of 20,30 and 50,respectively.The dimensions of the model rafts are 30 cm×30 cm with different thickness of 0.5 cm,1.0 cm or 1.5 cm.The raft-soil stiffness ratios of the model rafts ranging from 0.39 to 10.56 cover flexible to very stiff rafts.The improvement in the ultimate bearing capacity is represented by the load improvement ratio,LIR,and the reductions in average settlement and differential settlement are represented by the settlement ratio,SR,and the differential settlement ratio,DSR,respectively.The effects of the number of settlement reducing piles,raft relative stiffness,and the slenderness ratio of piles on the load improvement ratio,settlement ratio and differential settlement ratio are presented and discussed.The results of the tests show the effectiveness of using piles as settlement reduction measure with the rafts.As the number of settlement reducing piles increases,the load improvement ratio increases and the differential settlement ratio decreases.

Effect of reducing agents on reducing atmosphere in coal-based direct reduction of beach titanomagnetite

Beach titanomagnetite(TTM)provides a cheap alternative source of Fe and Ti,but this ore is difficult to process to make suitable concentrates for the blast furnace.Recently studies showed that it is feasible to separate Fe and Ti by coal-based direct reduction.In this study,beach TTM was selected as the research object,the effects of reducing agents on reducing atmosphere in coal-based direct reduction of beach TTM were analyzed,and the role of volatiles was also studied.The results showed that when bitumite and coke were used as reducing agents of TTM,the CO produced from volatiles was involved in the reduction reaction,and the generated CO_(2) provided the raw material for the reaction of TTM.The reduction effect of bitumite was better than that of coke.The reason is that bitumite+TTM had a higher gas generation rate and produced a higher CO partial pressure,while coke+TTM had a lower gas generation rate and produced a lower CO partial pressure.When graphite was used as a reducing agent,there was a solid-solid reaction in the early stage in the reaction.With the continuous accumulation of CO_(2),the Boudouad reaction started and accelerated.Graphite+TTM also produced a higher CO partial pressure.

Preparation of microencapsulatedα-olefin drag reducing polymer used in oil pipeline transportation

Microcapsules containing oil drag-reducing polymer particles were prepared by melting-scattering and condensing of polyethylene wax,in-situ polymerization of urea and formaldehyde,and interfacial polymerization of styrene respectively.The related processes were studied by a molecular dynamics simulation method,and molecular design of microcapsule isolation agent was carried out on the basis of the simulation.The technologies for preparing microencapsulated oil drag-reducing polymer particles were compared and the circulation drag reducing efficiency of the microencapsulated polymer particles was evaluated based on the characterization results and their dissolution properties.Molecular design of a microcapsule isolation agent suggests that a-olefin polymer particles can be stably dispersed in water by using long-chain alkyl sodium salt surfactant which can prevent the agglomeration ofα-olefin polymer particles.The results of simulation of the adsorption process shows that the amount of alkyl sodium salt surfactant can directly affect the stability of microencapsulatedα-olefin polymer particles, and there must be a minimum critical amount of it.After characterization of the morphology by Scanning Electron Microscopy（SEM） and comparison of the static pressure stability,especially the conditions of reaction and technological control of microcapsules with different shell materials,microencapsulation of a-olefin polymer particles with poly-（urea-formaldehyde） as shell material was selected as the optimum scheme,because it can react under mild conditions and its technological process can be controlled in a large range.The relationship of drag reducing rate and dissolving time of microcapsules showed that the formation of microcapsules did not affect the maximum drag reducing rate,and the drag reducing rate of each sample can reach about 35%along with the dissolving time,i.e.microencapsulation did not affect the drag reducing property ofα-olefin polymer.