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NADPH oxidase (NOX) is the only enzyme in the human body that can directly produce reactive oxygen species. Recent studies have shown that NADPH oxidase is a very potential target for the treatment of Diabetic Nephropathy (DN). Here, a series of quinoline (quinolinone) derivatives were designed and synthesized based on pharmacophore modelling. And the antiproliferative effect against NRK-49F cell-line was evaluated as their potential anti-DN activity. 19d, the most potent compounds with an effective cell proliferation inhibitory activity (IC50 = 5.25 uM), showed a promising inhibitory activity on NOXs (IC50 = 1.12 µM). The 3D-QSAR model based on the anti-proliferation activity of NRK-49F exhibited the good predictive ability. In conclusion, 19d may have therapeutic effects on diabetic nephropathy like other NOX inhibitors in clinical trials.

Attention allocation reflects the way of humans filtering and organizing the information. On one hand, different task scenarios seriously affect human's rule of attention distribution, on the other hand, visual attention reflecting the cognitive and psychological process. Most of the previous studies on visual attention allocation are based on cognitive models, predicted models, or statistical analysis of eye movement data or visual images, however, these methods are inadequate to provide an inside view of gaze behavior to reveal the attention distribution pattern within scenario context. Moreover, they seldom study the association rules of these patterns. Therefore, we adopted the big data mining approach to discover the paradigm of visual attention distribution.We applied the data mining method to extract the gaze patterns to discover the regularities of attention distribution behavior within the scenario context. The proposed method consists of three components, tasks scenario segmented and clustered, gaze pattern mining, and association rule of frequent pattern mining.The proposed approach is tested on the operation platform. The complex operation task is simultaneously segmented and clustered with the TICC-based method and evaluated by the BCI index. The operator's eye movement frequent patterns and their association rule are discovered. The results demonstrate that our method can associate the eye-tracking data with the task-oriented scene data.The proposed method provides the benefits of being able to explicitly express and quantitatively analyze people's visual attention patterns. The proposed method can not only be applied in the field of aerospace medicine and aviation psychology, but also can likely be applied to computer-aided diagnosis and follow-up tool for neurological disease and cognitive impairment related disease, such as ADHD (Attention Deficit Hyperactivity Disorder), neglect syndrome, social attention differences in ASD (Autism spectrum disorder).

Huang Lei,* Xingyou Dong,* Longkun Li,* Feng Huan, Xiao Zhong, Qingjian Wu, He Fang, Teng Zhang, Xinliang Yang, Jingzhen Zhu, Jia Li, Zhao Jiang Department of Urology, Second Affiliated Hospital, Army Military Medical University, Chongqing 400037, People’s Republic of China*These authors contributed equally to this workCorrespondence: Zhao JiangDepartment of Urology, Second Affiliated Hospital, Army Military Medical University, Chongqing 400037, People’s Republic of ChinaTel +86 23 68774624Email urologyzhaoj@sohu.comObjective: To explore the risk factors, pathogenic bacteria distribution and drug resistance of systematic transrectal ultrasound-guided prostate biopsy (TRUS-Bx), 329 cases of TRUS-Bx were collected, retrospectively, in the Second Affiliated Hospital, Army Military Medical University, from April 2017 to October 2019.Methods: A total of 329 cases were all qualified and grouped into the SIRS group (25 cases) and the non-SIRS group (304 cases). Of all the cases, incidence and risk factors of systemic inflammatory response syndrome (SIRS) were analyzed. Urine and blood samples of patients with SIRS after TRUS-Bx were also collected for bacterial culture and drug sensitivity test.Results: Multivariate logistic regression analysis showed that BMI ≥ 25 kg/m2 (OR = 1.66, 95% CI = 1.34– 2.12, P < 0.001), history of diabetes (OR = 5.48, 95% CI = 1.53– 19.68, P = 0.008), urinary infection before operation (OR = 9.19, 95% CI = 2.92– 20.93, P < 0.001) and erythrocyte sedimentation (ESR) ≥ 20 mm/h (OR = 1.04, 95% CI = 1.01– 1.08, P = 0.039) were independent risk factors of SIRS after TURS-PB.Conclusion: The incidence of SIRS and urinary sepsis was 7.59% and 2.13%, respectively, and major pathogens of SIRS after TRUS-Bx were Escherichia coli (58.33%), Klebsiella pneumoniae (12.5%) and Pseudomonas aeruginosa (12.5%). Imipenem, meropenem, tigecycline, piperacillin/tazobactam, teicoplanin, vancomycin, amikacin and cefoperazone/sulbactam had a very strong inhibitory effect to those pathogenic bacteria (sensitivity 85.72%∼ 100%). Levofloxacin, ciprofloxacin, gentamicin, penicillin G, compound neonomine and second-generation cephalosporins showed less but also worked as a good inhibitor to pathogenic bacteria (42.86%∼ 80.95%).Keywords: systematic transrectal ultrasound-guided prostate biopsy, systemic inflammatory response syndrome, prostate cancer, risk factors infection, pathogens

To evaluate the potential of using renewable biomass in the novel HIsarna technology, reactivity of thermal coal (TC), charcoal (CC), Bana grass char (BGC) before and after rapid devolatilization at 1500 °C in a drop tube furnace (DTF) was investigated. Thermogravimetric (TG) was used for CO2 gasification study, and high temperature confocal scanning laser microscope (HT-CSLM), Brunauer-Emmett-Teller (BET) and scanning electron microscopy (SEM) were used to characterise the morphology of all three raw carbonaceous materials and their chars produced by rapid devolatilization. CC has fastest gasification reaction before and after rapid heat treatment, and BGC raw is more reactive than TC raw but BGC 1500 °C and TC 1500 °C have very similar gasification behaviour. The reactivity index of the rapidly devolatilized char is reduced to 84.21% (BGC), 92.11% (TC) and 94.23% (CC) compared to their raw materials. This shows that BGC is more severely affected by the rapid devolatilization, and this behaviour is likely to be governed by the high ash content which will melt and cause pore blockage during heat treatment. According to HT-CSLM results the average particle sizes decreased by 28%, 24% and 20 % for TC, CC and BGC respectively. While the SEM images shown that TC has gone through significant structural changes during the rapid devolatilization, but CC and BGC maintained their parent structural shapes. The BET results indicate that TC is non-porous, but both CC and BGC contain a large number of constricted micropores with significantly larger surface area.

For low voltage ride through (LVRT) of the wind power generation system, rotor energy storage and super capacitor are promising options. When the rotor energy storage cooperates with the super capacitor for LVRT, the DC voltage will undulate violently due to the speed fluctuation. To solve this problem, a crowbar circuit topology and its control strategy including unloading resistance and super capacitor are proposed in this paper. During the process of LVRT, the super capacitor and resistor absorb energies together. In doing so, the DC bus voltage fluctuation will be suppressed by changing the value of the unloading resistance. The proposed method can effectively reduce the power of the unloading resistor and the capacity of super capacitor, and further decrease the hardware cost. By adding the penalty term of the current change rate to the cost function using the model predictive control method (MPC), the DC bus voltage fluctuation is reduced with the realization of rotor energy storage. The control performances of the proposed LVRT strategy are validated through simulation results.

With the rapid development of complex equipment, such as airplanes, the appropriate design of the human-machine interface is often upgraded, thus emerged many methods to evaluate whether such an upgrade is effective. Most researches focus on the time accumulation effect of the human state during the interaction to evaluate the interface. However, in the aviation application, the performance of the pilot’s instantaneous reactions also reveals the design efficiency of the interface, since the difficulty level of obtaining the useful information would severely influence the reaction time in some voice command tasks or emergency situations. Besides, there are so many flight scenarios that are impossible to be simulated in experiments or in a laboratory environment. Also, voice commands are too numerous to be traversed simulated. This paper introduced predicted auditory reaction time as an index to evaluate human-machine interface design. The proposed method has two advantages. On the one hand, it effectively measures the pilot’s auditory reaction time based on the eye movement tracking; thus, the data can be taken in flight task scenarios, and the experiment would not cause interference to the subjects. On the other hand, a prediction model is proposed, in which the pilot’s reaction time under more generalized voice command can be estimated based on a small-size sample set.

Surface oxidation of metallic powders may significantly affect their melting and solidification behavior and limit their service life in the additive manufacturing (AM) process. In the present work, three levels of surface oxide concentration were prepared on AM-grade 316L stainless steel powders, and their melting and solidification behavior was systematically studied through in-situ observation, advanced characterization, phase-field modeling, and theoretical analysis. Si, Mn, and Cr participated in the oxidation reaction in powder with low and medium oxygen contents, whereas Fe was involved in the oxidation reaction for the powder samples with high oxygen content. A higher full melting temperature is observed to lead to an integrated melt pool in the melting of the highly oxidized powder, which is due to the reduced permeability produced by the oxide cage effect. For the droplet samples prepared from high oxygen powders, the inclusion with increased volume fraction and coarsened size is attributed to the agglomeration of inclusion particles with the residual oxide in the melt. In the high oxygen powder fusion scenario, an undesired coarse columnar grain structure with a high aspect ratio is formed in the current nonequilibrium solidification process, and a consistent microstructure is predicted using solidification conditions with a high cooling rate and high thermal gradient similar to the conventional AM process. In contrast, fine equiaxed grains in the experiment and slim columnar grains with a small aspect ratio in the phase-field simulation are obtained for the low oxygen powder condition. This study illustrates the effect of powder oxide from a processing aspect and provides insight into the importance of improving the service life of powder feedstock by effectively reducing the surface oxidation process on the powder surface.

As the penetration of renewable energy increases a lot, the needs for novel grid topology and control strategy attracts researches. The breakthrough of power electronics makes the power transformation between multiple voltage levels or different current forms easier and cost lower. As for typical commercial building with on-site generation, this paper proposed a novel optimization method for power flow assigned to parallel- connected converters between two voltage levels for DC distribution. By the utilization of Lagrange Multiplier Method, the energy management system for those converters are corrected. In addition, several popular energy efficiency definitions are compared and analysed for choosing the most accurate one to carry on system evaluation. By combining normalized value of economic and efficiency index, the weighting factor based metric is used to compare the conventional AC distribution and DC distribution. Based on the time sequential simulation, the results show that under such novel optimization strategy, the energy efficiency is increased by 3.83% while the grid electricity saving is about 75.53 MWh accounting for 5% of the total annual load consumption.

The oxide evolution during the solidification of 316L stainless steel from additive manufacturing powders with different oxygen contents is studied by in situ observation of the melting and solidification of the powder materials, advanced characterization of the solidified materials, and non-equilibrium thermodynamic analysis. An oxide evolution map is established for the 316L powders with different oxygen contents. It reveals the relationship between the surface oxidation in the reused powder and its expected oxide species and morphology in the as-solidified component. For the 316L powder with oxygen content higher than ~ 0.039 pct, the liquid oxide formed first from the steel melt and then crystallized to certain oxide phases during solidification, while for the powder with lower oxygen, oxide phases are suggested to directly form from the steel melt. The oxide species in the as-solidified sample was predicted by the Scheil–Gulliver cooling calculation and verified by the TEM-based phase identification. The oxides formed in the melt of low O 316L alloy (0.0355 pct O) are predicted to be (Mn, Cr)Cr2O4 spinel and SiO2 oxide. In the high O (0.4814 pct O) 316L melt solidification, the final oxides formed are (Mn, Cr)Cr2O4 spinel, SiO2 oxide, and Cr2O3 corundum. As an important characteristic of powder materials, the oxygen pick-up due to the powder surface oxidation significantly influences the inclusion evolution in the powder fusion process.

The activation of non-basal pyramidal slip has been perceived as key to enhance the ductility of magnesium and its alloys. However, there has never been convincing evidence to show the physical existence of dislocations and their involvement in deformation has been a core issue in magnesium research. In the present work, the impossibility of slip is analyzed based on fundamental concepts of dislocation and atomic interactions. The atomic configurations and crystallographic features in association with dislocations are unambiguously revealed for the first time, demonstrating that any possible dislocation core structures would involve too many atoms on multiple lattice planes and are physically impossible. Experiments of magnesium single crystal compression along its c-axis were conducted at temperatures from 20°C to 500°C and the results showed no evidence of the involvement of dislocations in any form as a mechanism of deformation during either plastic flow or fracture. von Mises criterion for compatible deformation, which drives the pursuit of pyramidal slip, is critically discussed.

Unlike pulse width modulation (PWM) based approaches, the spectra of classical finite control set model predictive control techniques spreads uniformly across a wide frequency range for power converters, which makes the design of their filters particularly difficult. An effective method to achieve spectra similar to those of PWM for two-level power converters is the so-called model predictive period control (MPPC) approach, which makes the frequency of the converter’s output voltage quasi-fixed by adding a constraint on the switching frequency. In terms of output voltage change, voltage-state-change (VSC) is more relevant than switch-state-change (SSC) because the output voltage change is unequal to that of SSC for multi-level power converters. In this work we propose two different control techniques, namely, switch-state-change (SSC-MPPC) and voltage-state-change based model predictive period control (VSC-MPPC), for 3L-NPC power converters. Simulation data confirm that, i) both approaches achieve current spectra similar to those of PWM-based solutions, ii) both of them achieve quasi-fixed switch frequency, which simplifies the heat sink design, however, VSC-MPPC practically operates with half of the reference frequency for 3L-NPC converter, iii) SSC-MPPC outperforms the VSC-MPPC approach in terms of power quality and neutral point voltage regulation but consumes much more switching losses especially for high level power systems.

Euler angle analysis based on electron backscattered diffraction mapping technique was used to study the nucleation crystallography in SiC particulate reinforced AZ31 magnesium composite. Two sets of distinguishable and reproducible ORs between α-SiC 6H reinforcing particle and α-Mg matrix were experimentally identified as [ 2 ¯ 113] Mg //[10 1 ¯ 0] SiC , (10 1 ¯ 1) Mg //(0006) SiC , ( 2 ¯ 20 2 ¯ ) Mg //(1 2 ¯ 1 6 ¯ ) SiC and [1 1 ¯ 00] Mg //[01 1 ¯ 0] SiC , (0002) Mg //(0006) SiC , (11 2 ¯ 0) Mg //( 2 ¯ 110) SiC . Furthermore, the crystallographic matching between α-SiC 6H and α-Mg matrix was theoretically evaluated using Edge-to-edge matching (E2EM) model. The consistency between the predicted ORs and the experimental ORs verifies the good crystallographic matching between α-SiC 6H and α-Mg which therefore confirms the double effects of silicon carbide in the Mg/SiC p composite system as uniformly dispersed reinforcing phase in the matrix and moreover effective nucleation substrate of α-Mg grains.

Copyright The Authors 2017. Casting is the first step toward the production of majority of metal products whether the final processing step is casting or other thermomechanical processes such as extrusion or forging. The high shear melt conditioning provides an easily adopted pathway to producing castings with a more uniform fine-grained microstructure along with a more uniform distribution of the chemical composition leading to fewer defects as a result of reduced shrinkage porosities and the presence of large oxide films through the microstructure. The effectiveness of high shear melt conditioning in improving the microstructure of processes used in industry illustrates the versatility of the high shear melt conditioning technology. The application of high shear process to direct chill and twin roll casting process is demonstrated with examples from magnesium melts. Financial support from the EPSRC-UK through the funding of the EPSRC - LiME research centre for liquid metal engineering and contributions by Dr. Yubo Zuo, Dr. Mingxu Xia, and Dr. Hu-Tian Li are gratefully acknowledged.

Through analyzing the effect of configuration process on polymer solution, this study is to comprehensively evaluate the configuration effect of polymer solution from the aspects of its viscosity loss and mixing uniformity. It also puts forward a kind of evaluation coefficient with regard to the mixing uniformity of polymer solution and establishes an evaluation method of the configuration effect of polymer solution. The on-site experiment has proved that this method has accurate evaluation result with simple operation, and it is suitable to be promoted in the oil industry, and it provides a criterion for the design of the configuration process of polymer solution and the equipment selection.

In this Letter, we found that the growth of graphene on Cu oxide foil is significantly affected by the concentration of oxygen. The grain size of graphene grown on a Cu substrate with a relatively high oxygen concentration is much smaller than that on the substrate with lower oxygen concentration. By controlling the oxidation of the Cu substrate at a proper degree, we can obtain millimeter scale graphene single crystals at a growth temperature of 1050 °C. On the basis of our experimental observations, the dual role of oxygen in the CVD growth of graphene was revealed: (i) Oxygen on a Cu surface can contribute to the decomposition of hydrocarbon feedstock and decrease the graphene growth barrier, resulting in an increased growth rate and a larger grain size of graphene; (ii) excess oxygen in the Cu substrate leads to etching of the graphene edge. Our research provides insights to obtain large-area and single-crystalline graphene by choosing a proper Cu oxide substrate.

A novel melt conditioned twin roll casting (MCTRC) strategy with emphasis on solidification control has been investigated for producing thin gauge Mg alloy sheets ready for component forming, with the minimal requirement of down-stream processing. The performance of 1.5 mm thick AZ31 Mg alloy sheet is reported in this study to demonstrate the effect of the solidification control strategy on the microstructure and mechanical properties of the Mg alloy sheet produced by MCTRC process. The anisotropy of in-plane tensile properties of the AZ31 sheets is evaluated in association with characteristic features of solidification, deformation behaviour and texture evolution during the solidification control MCTRC process. The improved mechanical performance is attributed to the refined and uniform microstructure, reduced centre-line segregation and minimized deformation, which results in a weak basal texture. Keywords: Melt conditioning (MC), Twin roll casting (TRC), Solidification, Texture weakening, Mechanical properties, In-plane anisotropy

SiC particulate (SiCp) reinforced AZ31 magnesium alloy composite strips were produced by a novel process. In the process, a high shear technique was utilised to disperse the reinforcing particles uniformly into the matrix alloy, and AZ31/5vol%SiCp slurry was solidified into thin strip by a horizontal twin roll caster. The experimental results showed that the AZ31/5vol%SiCp strip obtained with high shear treatment exhibited a significantly refined microstructure and uniform distribution of reinforcing SiC particles. High cooling rate in the TRC process was also considered to contribute to the grain refinement of the matrix alloy, together with the possible heterogeneous nucleation effect of the reinforcing particles. The mechanical properties of the high shear treated composites strips showed enhanced modulus, yield strength and ductility by hardness and tensile tests. The experimental results were discussed in terms of the microstructural features and the macroscopic reliability, where necessary, analytical and statistical analyses were conducted. EPSRC UK, Towards Affordable, Close-Loop Recyclable Future Low Carbon Vehicle Structures (TARF-LCV), Grant No. EP/I038616/1.

SiC particulate reinforced A356 alloy metal matrix composites (MMCs) are synthesized using intensive melt shearing. The effect of reinforcing particle distribution on the fluidity of cast A356/10 vol.% SiCp composites is studied. Spiral length representing the fluidity of the composite melt was measured and liquid flow and solidification behaviour were analysed. Improvement in the fluidity of composites is attributed to the uniform distribution of reinforcing particles by intensive melt shearing treatment. From the casting performance point of view, uniform dispersion of reinforcing particles achieved with the aid of intensive shearing improves the mechanical properties of A356/10 vol.% SiCp cast composites. Improved strength, rigidity and wear resistance of composites is attributed to the bulk homogeneity, significantly reducing casting defects.

Twin roll casting (TRC) is recognised as an effective processing route for producing low cost Al sheet. However, the quality of the Al alloys sheets produced by the TRC process is limited by the formation of centre-line segregation which prevents its application in a wide range of engineering sectors. To improve the quality of the TRC strips, a new technology, melt conditioning twin roll casting (MC-TRC) has been developed from the industrial point of view. Enhanced nucleation by melt conditioning favours the advance of an equiaxed solidification front which results in reduced sump depth and a refined, uniform, defect free microstructure. The results obtained show that the differences in microstructure and in the crystallographic texture have a significant impact on ductility (22% improvement) of the MC-TRC sheets compared to TRC sheets.

The application of aluminium alloys in automotive body structure is one of the main developments in recent years. The increase of the mechanical properties of the ductile die-casting is one of the most critical topics for the application. In this work, the effect of melt superheating on the morphology, size and distribution of α-Al phase and Fe-rich intermetallics, and on the mechanical properties of the Al-Mg-Si-Mn diecast alloy was investigated. The results showed that the refined microstructure could be obtained through melt superheating. The volume fraction of dendritic α-Al phase and the Fe-rich intermetallic phase formed in the shot sleeve was significantly reduced, resulting in the refined microstructure. Overall, the melt superheating could improve the mechanical properties of the yield strength, ultimate tensile strength, and elongation of the diecast Al-Mg-Si-Mn alloy. And, the Fe-rich intermetallic phase formed in the shot sleeve with the coarse compact morphology and formed in the die cavity with the fine compact particles were identified as the same α-Al12(Fe,Mn)3Si composition in the present experimental conditions, which was not affected by the melt superheating. The financial support from Technology Strategy Board (TSB) under project No. 101172 is acknowledged. The authors also would like to thank the EPSRC (UK) and Jaguar Cars Ltd. (UK) for financial support under the grant for the EPSRC Centre - LiME.

In recent years BCAST has developed the high shear melt conditioning (HSMC) process for controlling solidification. HSMC is now an emerging technology to manipulate the solidification process by intensive shearing to control both the cast microstructure and defect formation. The high shear is applied to the melt using a simple rotor stator which has been demonstrated to disperse oxide films to provide a high density of oxide particles to enhance nucleation. The high-shear device has been successfully applied directly in the sump during DC casting up to the industrial scale to provide both significant grain refinement and uniform microstructure with reduced segregation and defects. It produces a DC casting sump with uniform chemical composition, uniform temperature, and a significantly increased temperature gradient at the solidification front. The sump temperature can be controlled by appropriate selection of the rotation speed. This provides the opportunity to control the cast microstructure, for example, to produce fine and uniformly dispersed second phase particles to improve mechanical properties. The high-shear device can also be used to degas alloys to unprecedentedly low hydrogen levels and has also been successfully applied to remove iron from casting alloys in which the iron containing particles are the primary solidification phase.

TRC Mg alloys are hot rolled to further reduce the thickness of the TRC strip which results in a sheet material with a relatively strong basal texture which produces anisotropic tensile properties based on the test direction. The low force TRC concept developed at BCAST provides a pathway to produce thin strip that does not require further hot rolling to achieve the final desired thickness. The as TRC and homogenised AZ31 show a refined grain and very little centre line. The as TRC AZ31 has a tensile yield strength of 220 MPa along the casting direction (CD) and 190 MPa perpendicular to CD showing a very small yield anisotropy.

Simultaneous reduction, repairing and doping of graphene oxide has been realized by the chemical vapor deposition method, using acetonitrile as a nitrogen source. A step-wise increase of acetonitrile partial pressure from 15 to 90 Pa results in nitrogen doped graphene (NG) with gradually tuning N-doping concentration from 0.38 to 0.66 at% and systematically rising graphite-N ratio from 23.25 to 45.39%, which in turn modulates field emission performance and enhance the stability. Raman spectroscopy and X-ray photoelectron spectroscopy suggest pyrrolic-N and pyridinic-N doping bring defects, while defects decrease as N-doping concentration increases due to the rising of graphite-N ratio. Proper defects may increase emission site density and N-doping can reduce work function. When N-doping concentration is controlled at 0.42 at%, NG exhibits the considerable decreasing of turn-on field from 3.35 to 2.18 V/μm at the emission current of 10 μA/cm2 and increasing of field enhancement factor from 1835 to 2967. It also reveals a good field emission stability with no degradation, which is superior to pristine reduced GO emitters. It is suggested the NG with tuning concentration of three type nitrogen emitter is a widely candidate for various field emission devices and applications.

Reduced graphene oxide bundles with sharp tips were fabricated by a simple approach with freeze-drying and hydrothermal reduction, and this approach could modify the surface topography of the field emission cathode and make more graphene bundles sharpen and aligned. This field emission cathode material displayed excellent field emission properties decreased from 2.9 V μm−1 to a low turn-on field of 0.8 V μm−1 at the emission current density of 10 μA cm−2. Sharp graphene emitter arrays have sharp protruded tips in abundance, leading to an enlarged field enhancement factor from 1683 to 10182, which was much better than those films prepared by other methods we adopted. It also revealed a good field emission stability with no degradation in the current for 3 h. We believe that this approach can enhance the field emission performance of graphene emitters, which could be widely candidate for various field emission applications.

Identifying remaining oil distribution is an essential study at the Third District in North Saertu of the West Block in Daqing Oilfield. This field is known as a flooding fine potential tapping demonstration zone, characterized by a long-developing history and complex well history. Based on tectonic features and sedimentary characteristics of the study area, the methods of facies controlled reservoir 3D geological modeling and numerical simulation are used in the process of establishing the geological 3D static model. In this paper, we summarized the causes and distribution law of remaining oil in the study area by using the method of fine reservoir numerical simulation to provide a reliable basis for the development and adjustment of the oil field. In combination with fine exploration such as water drive fracturing, water plugging, reperforating and injection-production segment, the recoverable reserves recovery rate could be effectively increased. Estudio de la distribución del remanente de petróleo en el bloque oriental del tercer distrito, en el norte de Sartu, China ResumenLa identificación de la distribución del remanente de petróleo es un estudio esencial en el tercer distrito del norte de Sartu, que corresponde al bloque occidental del campo petrolífero de Daqing. Este campo es conocido como una zona ejemplar para aprovechar el potencial de explotación por inundación y que se caracteriza por una historia compleja y de largo desarrollo de sus pozos. Con base a las características tectónicas y sedimentarias del área de estudio se utlilizaron los métodos de modelado geológico 3D en depósitos con facies controladas y la simulación numérica en el proceso de establecer el modelo geológico 3D estático. En este artículo se establecen las causas y la ley distributiva del remanente de petróleo en el área de estudio a través del método de simulación numérica de depósitos de alta resolución que provea una base fiable para el desarrollo y ajuste del campo petrolero. Con la combinación de métodos de exploración como la fractura dirigida con agua, taponamiento acuático, reperforación y segmentos de inyección-producción, el índice de recuperación de reservas podría incrementar efectivamente.

This study revisits rhetorical variations in the introductions of experimental research articles between Chinese and Anglo-American materials scientists by utilizing QSR NVivo2. Rhetorical underdevelopment can be observed at the high generic-structure level of discoursal move in Chinese texts but not necessarily so at the subordinate generic-structure level of step. A couple of rhetorical steps like Claiming Centrality bear evident deviations from our traditional understanding of non-Anglophone scientific writing in that the disciplinary community of Chinese materials science has undergone drastic changes in its social context but at the same time embraces its own distinct community heterogeneity and knowledge gap in knowledge negotiation.