Complexity of Injective Homomorphisms to Small Tournaments, and of Injective Oriented Colourings

Several possible definitions of local injectivity for a homomorphism of an oriented graph G to an oriented graph H are considered. In each case, we determine the complexity of deciding whether there exists such a homomorphism when G is given and H is a fixed tournament on three or fewer vertices. Each possible definition leads to a locally-injective oriented colouring problem. A dichotomy theorem is proved in each case.

Horizontal Well Interference Performance and Water Injection Huff and Puff Effect on Well Groups with Complex Fracture Networks:A Numerical Study

Well interference has become a common phenomenon with the increasing scale of horizontal well fracturing.Recent studies on well interference in horizontal wells do not properly reflect the physical model of the postfracturing well groups and the realistic fracturing process of infill wells.Establishing the correspondence between well interference causative factors and manifestations is of great significance for infill well deployment and secondary oil recovery.In this work,we develop a numerical model that considers low velocity non-Darcy seepage inshale reservoirs to study the inter-well interferencephenomenon that occurs in theSantanghufield,andconstruct an explicit hydraulic fracture and complex natural fracture network model with an embedded discrete fracture model,focusing on the effect of fracture network morphology on well interactions.The model also considers a multi-segment wellbore model to accommodate the effect of inter-well crossflow on wellbore tubular flow.The changes in formation pressure and water saturation during fracturing are performed by controlling the injection pressure and water injection rate.The result shows that the shape of the fracture network generated by the infill well with the old well determines the subsequent fluid and oil-increasing performance of the disturbed well.The synergistic production or competitive relationship formed by fractures with different connectivity between the two wells determines the positive and negative effects of the interference.The paper also investigates the adaptation study of water injection huff and puff schemes for well groups with different connectivity,and demonstrated a potential yield increase of up to 10.85%under adaptation injection.This method of identifying well interference based on the production dynamics of affected wells and the subsequent corresponding water injection method provides valuable references for the selection of secondary oil recovery measures.

Layered injection technology for chemical flooding of Class-Ⅲ oil reservoirs in the Daqing Oil Fields complex,Songliao Basin,Northeast China

The Class-Ⅲ oil reservoirs of Lasaxing oilfield in the Daqing Oil Fields complex have geological oil reserves of 1.86 billion tonnes,an oil recovery of 39%,with remaining reserves accounting for more than 45%of the total geological reserves of the oilfield.Therefore,they have considerable potential for future oil production.The current layered injection technologies fail to achieve effective control over the low single-layer injection rates since they can only produce low throttle differential pressure under low injection rates(5-20 m^(3)/d).In this study,a symmetrically-structured double-offset-hole injection allocator and a novel throttling component were developed.Their spatial layout was constructed and mechanical parameters were optimized using finite element analysis,which allows for expanding the flow rate range at low injection rates.According to experimental results,the throttle differential pressure increased from 0.2 MPa to 0.8 MPa at an injection rate of 5 m^(3)/d,and the range of the single-layer flow rates expanded from 20-70 m^(3)/d to 5-70 m3/d.The field test results show that the effective production of oil layers with medium and low permeability was achieved and that the ratio of producing oil layer thickness to the total reservoir thickness increased by 9.7%on average.Therefore,this study provides valuable technical support for the effective chemical-flooding-based development of Class-Ⅲ oil reservoirs.

n-FI内射复形及其性质

将n-FI内射模推广到复形层面.首先,给出n-FI内射复形的定义;其次,证明复形C是n-FI内射复形当且仅当每个层次是n-FI内射模,且对任意FP-内射维数不超过n的复形X,复形Hom(X,C)正合;最后,利用复形的覆盖刻画n-FI内射复形.

基于光学定位的三维超声引导肌肉注射仪设计研究

目的解决光学定位技术在引入肌肉痉挛治疗的注射手术应用中,光学定位设备与现有医用超声仪器之间的不适配问题,旨在进一步提升理论定位精度稳定性,简化必需操作并降低实际应用难度。方法在现有超声仪及相关设备功能基础上,结合光学定位设备工作条件需求进行需求分析,重新构建产品元件功能流模型并映射为网络节点,并基于复杂网络节点重要度评价方法,确定目标产品设计重心点并分层设计,最后采用仿真验证测试设计合理性。结果实验结果符合预期假设,目标节点所对应功能元件与其它节点的相关性程度与目标元件所需兼容连接的复杂度呈正相关。基于实验得出能够适配光学定位仪与超声设备的设计方案,有效解决二维超声导航引导肌肉注射所面临的不直观、不可视等问题。结论基于复杂网络节点的重要度评价方法更适用于复杂功能产品的设计研究,评价结果重要度差异更为显著。

深井超深井注入过程井筒温度场模型研究及应用

低温流体的注入过程若使井筒温度场发生较大变化,管柱会因温度变形而产生较大的附加轴向力,导致管柱变形和封隔器失封。为此,考虑深井、超深井井身结构特点及地层传热机理,根据能量守恒定律和热力学定律,建立深井、超深井注入过程井筒温度场模型。采用稳态假设消除时间项并连续使用解析法得到模型解析解,结合某超深井井身结构与施工参数,分析了复杂井身结构和地层温度对计算结果的影响,得到了不同注入温度和排量下井筒温度分布规律。研究结果表明,考虑复杂井身结构后模型精度更高,与井底温度的绝对误差为-0.56%,不考虑复杂井身结构的绝对误差为1.52%;地层温度对井筒温度的影响较小。研究结果可为管柱力学分析提供数据支撑、为作业参数优化提供理论依据。

复杂螺纹结构瓶盖热流道注塑模

针对一种复杂螺纹结构瓶盖,分析了它的结构特征,采用热流道注塑模设计方案,使流道内熔体保持恒定温度,经CAE分析优化流道方案,设计了一模四腔热流道注塑模具。瓶盖内部采用了模内机动螺纹和组合式型芯结构、推管推出机构。模具设计结构合理,开合模动作可靠,制品顺利脱模,自动化程度高,塑件精度高。产品达到客户要求,有效解决了目前热流道工艺上所存在的缺陷,为同类模具结构设计提供一定的参考。

强Gorenstein AC-内射复形及维数

设n为任意整数,引入并研究了强Gorenstein AC-内射复形,证明了复形X是强Gorenstein AC-内射复形当且仅当Xn是Gorenstein AC-内射模,且对任意的DG-绝对clean复形A,复形同态f:A→X是零伦的。特别地,若X为有界正合复形,则X的强Gorenstein AC-内射性等价于模Z_n(X)的Gorenstein AC-内射性,也等价于模Xn的Gorenstein AC-内射性。此外,引入并研究了复形的强Gorenstein AC-内射维数。

多糖铁复合物胶囊联合重组人促红素注射液治疗肾性贫血的效果

目的 探讨多糖铁复合物胶囊联合重组人促红素注射液治疗肾性贫血的临床效果。方法 选取2020年3月至2023年2月我院收治的100例肾性贫血患者,按照抽签法分为观察组与对照组。对照组采用重组人促红素治疗,观察组采用多糖铁复合物胶囊联合重组人促红素治疗。比较两组的治疗效果、血清指标及不良反应。结果 观察组总有效率为88.00%,高于对照组的64.00%(P <0.05)。治疗后,观察组血红蛋白(Hb)、白蛋白(Alb)、转铁蛋白(SF)、血细胞比容(Hct)水平高于对照组(P <0.05)。观察组血压升高、肝肾功能异常、胃肠功能减弱、发热发生率均低于对照组(P <0.05)。结论 多糖铁复合物胶囊联合重组人促红素注射液治疗肾性贫血的效果较好,可改善患者临床指标水平,降低不良反应发生率。

A novel profile modification HPF-Co gel satisfied with fractured low permeability reservoirs in high temperature and high salinity

Conformance control and water plugging are a widely used EOR method in mature oilfields.However,majority of conformance control and water plugging agents are unavoidable dehydrated situation in high-temperature and high-salinity low permeability reservoirs.Consequently,a novel conformance control system HPF-Co gel,based on high-temperature stabilizer(CoCl_(2)·H_(2)O,CCH)is developed.The HPF-Co bulk gel has better performances with high temperature(120℃)and high salinity(1×10^(5)mg/L).According to Sydansk coding system,the gel strength of HPF-Co with CCH is increased to code G.The dehydration rate of HPF-Co gel is 32.0%after aging for 150 d at 120℃,showing excellent thermal stability.The rheological properties of HPF gel and HPF-Co gel are also studied.The results show that the storage modulus(G′)of HPF-Co gel is always greater than that of HPF gel.The effect of CCH on the microstructure of the gel is studied.The results show that the HPF-Co gel with CCH has a denser gel network,and the diameter of the three-dimensional network skeleton is 1.5-3.5μm.After 90 d of aging,HPF-Co gel still has a good three-dimensional structure.Infrared spectroscopy results show that CCH forms coordination bonds with N and O atoms in the gel amide group,which can suppress the vibration of cross-linked sites and improve the stability at high temperature.Fractured core plugging test determines the optimized polymer gel injection strategy and injection velocity with HPF-Co bulk gel system,plugging rate exceeding 98%.Moreover,the results of subsequent waterflooding recovery can be improved by 17%.

改进电机全速域无位置传感器转速控制系统研究

针对宽速电机的全速域应用场景,提出改进传统加权平均法,并利用改进后的中高速域滑模观测器法和低速域脉振高频注入法进行复合,实现精确的全速域无位置传感器控制。首先,针对滑模观测器法中符号函数导致的系统抖振,提出指数型复合函数用来替代原观测器中的符号函数;其次,针对脉振高频注入法中高频电流分量与注入信号的相位延迟,提出使用另一轴系高频电流替代注入信号;再次,针对加权平均法在过渡区域的权重分配不合理,提出新型指数型加权系数,同时为平稳过渡提出滞留缓冲带;最后,在MATLAB/Simulink仿真平台搭建基于滞留缓冲加权法的全速域转速控制系统,进行仿真验证。通过仿真结果,表明了改进后的全速域转速控制系统对转速误差和平稳过渡的优化效果。

南海西部复杂断块低渗油田开发技术进展及发展方向

南海西部复杂断块低渗油田整体储量规模大,是南海西部油田下一步产能接替的重点靶区,但断块小、油藏埋深大,储层复杂,高效开发难度大。针对储层非均质性强,平面储层变化快,储层物性主控因素复杂问题,采用精细油藏描述技术精准预测“甜点”储层的展布,为低渗储层开发井的部署指引方向;为解决低渗油藏水敏严重常规注海水开发效果差难题,攻关注气重力辅助驱及纳滤海水驱替技术,建立低渗油田有效驱替技术系列,完善注采井网,提高驱替效果;为应对海上平台井槽资源受限问题,采用少井高产技术,利用复杂结构井,有效提高单井波及范围。同时,研发低渗油田高效开发配套技术,整合资源,盘活内部及周边区域潜力,为南海西部油田上产稳产奠定坚实的技术基础。

复杂条件下回采巷道矿压治理实践

为解决3914大采高综采面近距离煤层开采、沿空留巷、采空区边界煤柱、孤岛工作面等复杂条件下的巷道围岩控制难题,根据现场生产地质条件,通过理论分析和现场实测,对巷道矿压显现规律进行了分析,提出了采用“卸压+锚网索+注浆+架棚”等联合支护方式等主被动联合支护方式,保证了工作面的正常推进,安全高效回收了30 m区段护巷煤柱。实践表明:煤岩体协同控制结构是巷道围岩控制的关键,锚注一体化、主被动联合支护对复杂条件下的巷道围岩控制效果较好。

复杂结构零件免喷涂工艺的研究应用

对带孔状结构零件采用精密高光注塑工艺,运用免喷涂材料,实现外观颜色件的成型,达到汽车造型设计要求,同时实现了整车成本的降低,满足了电动汽车绿色出行的设计理念。通过采用独立模温控制的针阀热流道设计,解决了带孔状复杂结构零件的熔接线问题,同时改进金属粉的形状和颗粒大小,结合高温成型,解决了表面流痕,达到A级表面效果。

Application study on complex wetting agent for dust-proof after gas drainage by outburst seams in coal mines

After gas drainage,the outburst seam is dry and,consequently,during subsequent mechanized mining,unwanted dust production is extensive.Because the hard dustfall typically has a small particle size it contains a high percentage of respirable dust.Considering these factors,this paper improved the efficiency of dustfall by reducing the surface tension of the liquid used as a wetting agent,then configuring five kinds of wetting agents by adopting various doses and types of surfactants,neutral inorganic salts and chemical additives,etc.After purchasing DA-85 and SRJ-1 wetting agent,the surface tension and critical micelle concentration of seven kinds of wetting agents were measured using the capillary rise method.Wetting agent A was confirmed to have the best comprehensive effect.The experiments were optimized by measuring and comparatively analyzing contact angles of pure water,SRJ-1 wetting agent and wetting agent A on the surface of different coal samples using a contact angle measurement instrument(HARKESPCA).By comparative analysis,dust-proof effects of seam,dynamic pressure water infusion and highpressure spray in the tunneling face at the Daning coal mine using pure water,wetting agent SRJ-1and A,it was determined that after using wetting agent A,the average dust concentration in the place of the mining machine driver,10 m and 110 m away from the tunneling front is approximately 300 mg/m^3,240 mg/m^3 and 100 mg/m^3,respectively.This practice increased the dust-proof efficiency dramatically and achieved a good comprehensive dust-proof effect.

Improvement of electron injection of organic light-emitting devices by inserting a thin aluminum layer into cesium carbonate injection layer

We investigate the electron injection effect of inserting a thin aluminum（Al） layer into cesium carbonate（Cs2CO3）injection layer. Two groups of organic light-emitting devices（OLEDs） are fabricated. For the first group of devices based on Alq3, we insert a thin Al layer of different thickness into Cs2CO3 injection layer, and the device＇s maximum current efficiency of 6.5 cd/A is obtained when the thickness of the thin Al layer is 0.4 nm. However, when the thickness of Al layer is 0.8 nm, the capacity of electron injection is the strongest. To validate the universality of this approach, then we fabricate another group of devices based on another blue emitting material. The maximum current efficiency of the device without and with a thin Al layer is 4.51 cd/A and 4.84 cd/A, respectively. Inserting a thin Al layer of an appropriate thickness into Cs2CO3 layer can result in the reduction of electron injection barrier, enhancement of the electron injection, and improvement of the performance of OLEDs. This can be attributed to the mechanism that thermally evaporated Cs2CO3 decomposes into cesium oxides, the thin Al layer reacts with cesium oxides to form Al–O–Cs complex, and the amount of the Al–O–Cs complex can be controlled by adjusting the thickness of the thin Al layer.

复杂断块油藏水驱储量控制程度评价新方法

复杂断块油藏纵向上油层多,平面上油砂体发育面积小,平面非均质性强,难以构建规则井网均匀驱替,同时受储层各种封闭边界影响,水驱过程中易形成死油区,为了更加精准计算水驱储量控制程度,更好地评价油藏的井网合理性与完整性,找出井网调整和加密潜力,针对常规方法的不足,提出了更加适用的新方法,即网格储量法。通过提高平面上井网内储量控制面积的划分精度,结合储层地质条件及储层非均质差异,以注采井组为基本单元,逐层网格化井网控制地质储量,对网格化的地质储量进行分类统计,找出复杂边界造成的死油区,进而计算区块注采井网控制程度、水驱储量控制程度,最终得到井网调整加密潜力。将该方法应用在南堡101断块井网适应性评价中,找到了复杂边界造成的井网未控制未动用区域,通过加密调整取得较好的挖潜效果,证明该方法在复杂断块油藏水驱储量控制程度评价有较好的适应性,可以推广至其他复杂断块油藏。

基于CAD/CAE技术的复杂面板注塑模具设计研究

我国机械及电子工业产品的开发设计,离不开模具技术对三维实体模型结构的建设,而计算机辅助设计(Computer Aided Design,CAD)、计算机辅助工程(Computer Aided Engineering,CAE)等软件技术,在现代模具设计中发挥着越来越重要的作用。围绕复杂面板注塑模具设计与制造的执行流程,针对模具成型存在的周期不确定、制件翘曲变形、冷却质量偏差等问题,利用CAD/CAE软件技术,开展模具三维结构、注塑工艺等的设计与优化,建构起复杂塑件的浇注系统、冷却导热系统,以保证复杂面板注塑模具产品的生产质量。

复杂油气藏型地下储气库气藏工程关键参数设计方法

我国地下储气库(以下简称储气库)建库目标包括复杂断块、强水侵、异常高压、高含油凝析气藏等复杂类型,普遍具有埋藏深、构造复杂、储层物性差、非均质性强等特点。常规气藏工程参数设计方法不适用,尤其在圈闭密封性分析、库容参数设计及注采能力评价等方面具有一定特殊性。为此,从建库目标地质特征出发,通过聚焦难点、自主创新、攻克技术瓶颈,形成了复杂断块储气库四维动态密封性评价技术,建立了异常高压储气库库容参数预测方法及水侵储气库分区带多因素耦合注采能力预测模型,论证了凝析气藏“提采—协同—储气”建库新模式和优化技术对策。研究结果表明:①通过物理模拟实验揭示了复杂断块储气库盖层疲劳损伤和断层滑移机理,实现了动态密封性指标定量化评价,为复杂断块型储气库库址筛选奠定了基础;②针对超高压裂缝型储气库岩石强应力敏感特性,建立了考虑压缩系数变化和束缚水膨胀的有效库容预测新方法,并形成了考虑周期时变和水侵影响的强水侵储气库不同区带多周期注采能力预测方法,实现了建库参数科学设计;③建立了凝析气藏提高采收率协同储气库建设新模式,明确了“提采—协同—储气”合理转换时机,形成了分阶段建库参数设计方法和井网部署对策。结论认为,形成复杂油气藏型储气库气藏工程关键参数设计系列方法有力支撑了中国石化复杂油气藏型储气库建设和运行,并对同类储气库建设具有指导作用。

局部注射维生素C方案预防复杂区域疼痛综合征的效果分析

目的探讨局部注射维生素C方案预防复杂区域疼痛综合征(CRPS)的效果。方法80例接受桡骨远端骨折切开复位内固定患者,根据预防方案不同分为A组、B组、C组、D组,各20例。A组在缝合完毕后于骨折断端局部注射5 ml 0.9%生理盐水,B组局部注射125 mg维生素C+5 ml 0.9%生理盐水,C组局部注射250 mg维生素C+5 ml 0.9%生理盐水,D组局部注射500 mg维生素C+5 ml 0.9%生理盐水。比较四组CRPS发生率,干预前后的视觉模拟评分法(VAS)评分,疼痛缓解效果。结果A组CRPS发生率为50.00%,B组CRPS发生率为20.00%,C组CRPS发生率为0,D组CRPS发生率为0。B组、C组、D组CRPS发生率低于A组,C组、D组CRPS发生率低于B组,差异有统计学意义(P<0.05)。干预后,四组VAS评分均较干预前降低,且B组VAS评分(3.52±1.01)分、C组(3.21±1.22)分、D组(1.52±0.25)分低于A组的(4.25±1.07)分,D组低于B组、C组,差异有统计学意义(P<0.05)。干预后,B组、C组VAS评分比较差异无统计学意义(P>0.05)。A组疼痛缓解优良率为35.00%,B组为70.00%,C组为70.00%,D组为95.00%。B组、C组、D组疼痛缓解优良率高于A组,D组高于B组、C组,差异有统计学意义(P<0.05)。B组、C组的疼痛缓解优良率比较,差异无统计学意义(P>0.05)。结论对桡骨远端骨折切开复位内固定患者在切口缝合完毕后于骨折断端局部注射500 mg维生素C+5 ml 0.9%生理盐水能缓解患者疼痛程度,降低CRPS发生率,值得进一步在临床推广以及应用。