High-Gain Array Antenna Based on Composite Right/Left-Handed Transmission Line

In this paper a metamaterial-inspired antenna with high gain and good directivity is designed. Based on the concept of composite right/left-handed transmission line (CRLH-TL), the proposed antenna is realized based on three leakage wave unit cell and a left handed circular ring slot incorporated on the surface. The maximum achievable gain at the resonant frequency of 5.6GHz is 6.933 dBi, and the return loss at 5.6 GHz can be –20 db. This proposed design has a simple structure and a compact dimension of 35 mm*40 mm*1 mm, which is suitable for particular wireless communication application such as WiFi and WLAN.

Design of Miniaturized Band-Pass Filter with Composite Right/Left-Handed Transmission Line

In this paper, a new miniaturized wide-pass-band filter at U band based on composite right/left- handed transmission line (CRLH TL) is implemented. The CRLH TL contributed to a broadband filter is a balanced structure with a small size of only 1.428 mm*0.5530 mm. The frequency characteristics are simulated and the results show that the 3 dB band width of the proposed filter is about 13.5 GHz from 45.8 GHz to 59.3 GHz. The insertion loss is quite flat through the pass-band and the return loss is relatively low.

Magnetic properties of soft layer/FePt-MgO exchange coupled composite perpendicular recording media

The magnetic properties of exchange coupled composite （ECC） media that are composed of perpendicular magnetic recording media FePt MgO and two kinds of soft layers have been studied by using an x-ray diffractometer, a polar Kerr magneto-optical system （PMOKE） and a vibrating sample magnetometer （VSM）. The results show that ECC media can reduce the coercivities of perpendicular magnetic recording media FePt-MgO. The ECC media with granular-type soft layers have weaker exchange couplings between magnetic grains and the magnetization process, for ECC media of this kind mainly follow the Stoner Wohlfarth model.

Investigation of L1_0 FePt-based soft/hard composite bit-patterned media by micromagnetic simulation

The soft/hard composite patterned media have potential to be the next generation of magnetic recording, but the composing modes of soft and hard materials have not been investigated systematically. L10 FePt-based soft/hard composite patterned media with an anisotropic constant distribution are studied by micromagnetic simulation. Square arrays and hexagonal arrays with various pitch sizes are simulated for two composing types： the soft layer that encloses the hard dots and the soft layer that covers the whole surface. It is found that the soft material can reduce the switching fields of bits effectively for all models. Compared with the first type, the second type of models possess low switching fields, narrow switching field distributions, and high gain factors due to the introduction of inter-bit exchange coupling. Furthermore, the readout waveforms of the second type are not deteriorated by the inter-bit soft layers. Since the recording density of hexagonal arrays are higher than that of square arrays with the same center-to-center distances, the readout waveforrns of hexagonal arrays are a little worse, although other simulation results are similar for these two arrays.

Wave transmission through laminated composite double-walled cylindrical shell lined with porous materials

A study on free harmonic wave propagation in a double-walled cylindrical shell, whose walls sandwich a layer of porous materials, is presented within the framework of the classic theory for laminated composite shells. One of the most effective components of the wave propagation through the porous core is estimated with the aid of a flat panel with the same geometrical properties. By considering the effective wave component, the porous layer is modeled as a fluid with equivalent properties. Thus, the model is simplified as a double-walled cylindrical shell trapping the fluid media. Finally, the transmission loss （TL） of the structure is estimated in a broadband frequency, and then the results are compared.

Broadband microwave frequency doubler based on left-handed nonlinear transmission lines

A bandwidth microwave second harmonic generator is successfully designed using composite right/left-handed non- linear transmission lines （CRLH NLTLs） in a GaAs monolithic microwave integrated circuit （MMIC） technology. The structure parameters of CRLH NLTLs, e.g. host transmission line, rectangular spiral inductor, and nonlinear capacitor, have a great impact on the second harmonic performance enhancement in terms of second harmonic frequency, output power, and conversion efficiency. It has been experimentally demonstrated that the second harmonic frequency is deter- mined by the anomalous dispersion of CRLH NLTLs and can be significantly improved by effectively adjusting these structure parameters. A good agreement between the measured and simulated second harmonic performances of Ka-band CRLH NLTLs frequency multipliers is successfully achieved, which further validates the design approach of frequency multipliers on CRLH NLTLs and indicates the potentials of CRLH NLTLs in terms of the generation of microwave and millimeter-wave signal source.

CO_(2)快速吞吐提高页岩油采收率现场试验

页岩油注CO_(2)吞吐提高采收率技术处于探索阶段,目前面临着CO_(2)与页岩储层及流体相互作用机制不明确、数值模拟技术不成熟、缺乏规模注采及低成本回收工艺等技术难题。为探索页岩油注CO_(2)提高采收率主控机理,以苏北盆地溱潼凹陷古近系阜宁组二段页岩油为对象开展了超临界CO_(2)水岩反应实验,分析了高温高压条件下页岩矿物溶蚀作用及其对孔隙度和渗透率的影响,并通过注CO_(2)恒质膨胀实验、最小混相压力测试评价了地层超压条件下注CO_(2)后原油高压物性变化特征,并在此基础上开展考虑多因素数值模拟研究优化了设计注入参数,最终通过矿场试验验证了技术可行性。研究结果表明:(1) CO_(2)水岩反应以碳酸质矿物溶蚀占主导,长英质矿物部分溶解,生成中大孔隙;(2)在地层原油中注入适量的CO_(2),显著萃取了原油中间烃组分,原油黏度从5.151 mPa·s下降到1.250 mPa·s,且CO_(2)首先萃取轻烃组分,随生产时间增加萃取组分逐渐变为重烃;(3)基于人工压裂与天然缝网混合介质组分数模模型,优化设计单井吞吐注气量1.7×10~4 t,注气速度500~600 t/d,焖井时间50 d;(4)低压侧加热的页岩油CO_(2)吞吐地面工艺,可依据CO_(2)注入地面工艺多参数数据模型,实现精准控温,避免注入管线冻堵及井下油管和套管材料低温脆断问题;(5)产出气CO_(2)浓度高于80%时,采用气相回收直注工艺,实现产出气回收成本降至104元/t。结论认为,CO_(2)快速吞吐有效提高了页岩油采收率,形成的机理认识和技术系列可为页岩油注CO_(2)吞吐开发提供参考和借鉴。

基于壳聚糖的复合抑菌空气滤料制备与评估

由于新冠疫情的暴发,人们对于室内空气质量有了更高的要求.探索既能过滤细微颗粒物,还能抑制和消杀微生物细菌、防止二次污染的过滤材料具有重要意义.以质量分数为1%的聚四氟乙烯(PTFE)乳液配制出不同壳聚糖质量浓度的浸渍液,利用直接浸渍后处理工艺制备出壳聚糖/涤纶/聚四氟乙烯复合抑菌空气滤料.利用大肠杆菌为实验菌落验证其抑菌性能,并对其织物特性、捕集效率及压差特性进行了研究.结果表明,壳聚糖质量浓度为12.5 mg/mL时复合滤料初始阻力最小,对PM_(2.5)粒子捕集效率达到93.88%,品质因子为0.02013,分别比原始滤料提高19.56%,0.0044,且对大肠杆菌的抑菌率为84.12%.综上所述,壳聚糖质量浓度为12.5 mg/mL,PTFE乳液质量分数为1%的浸渍液制备的壳聚糖/涤纶/聚四氟乙烯复合抑菌空气滤料兼具良好的过滤能力与抑菌效果.

文化传媒企业价值评估综述

随着人们物质生活的丰富,精神文明的重视程度也逐渐增加。文化传媒企业对社会经济拉动作用不断增强,对于文化传媒企业价值评估的关注也随之提高。文章运用文献计量法和内容分析法,梳理归纳文化传媒企业价值构成和评估方法,多维度比较多个评估方法,指出现有研究的不足之处,展望今后可行的优化途径,为文化传媒企业价值评估的理论研究和实际应用提供指导意义。

烹饪方法对食材营养成分的影响研究

本文分析了煮、蒸和炒3种常见烹饪方式对食材营养成分的影响,发现煮易导致蛋白质变性、脂肪氧化和维生素流失,蒸虽能保留部分矿物质,但维生素C损失严重,而炒可能导致蛋白质和脂肪的过度破坏。为保护食材营养,提出了低温烹调、合理搭配酸碱介质、优化烹饪时间与火候的策略。这些措施旨在减少烹饪过程中营养成分的损失,提高食物的营养价值,为人们提供科学的烹饪建议。

Propagation of Elastic Plane Waves in Homogeneous Anisotropic Media

Combining the linear transformation and the solution technique for the cubic equation, a general closed-form analytic solution for bulk waves in orthotropic anisotropic materials is obtained. This method is straightforward and general. Degenerated cases include transversely isotropic, cubic, and isotropic materials. Numerical computations are carried out on a fiber-reinforced composite plate modeled as a transversely isotropic media. The fibers are parallel to the top and bottom surfaces of the plate, and they are rotated counterclockwise around the plate normal through different angles. The two-dimensional slowness curves corresponding to different rotations are presented graphically. The wave propagation characteristics displayed in slowness surfaces for different fiber orientation are analyzed. Key words composite material - anisotropic media - wave propagation - slowness PASC 2001 0343.8 - 042 Project supported by the Science Foundation of Shanghai Municipal Commission of Education (Grant No. 03AK48)

乡村旅游景观廊道湿地水体净化处理及循环再生利用研究

针对乡村旅游景观廊道湿地水体污染物去除率低的问题,研究乡村旅游景观廊道湿地水体净化处理及循环再生利用。建立回归分析模型,明确水体污染物总量。根据净化需求布置石墨烯和纳米材料,展开光催化氧化降解处理。搭建复合介质人工浮岛,模拟水体流速调整浮岛结构参数,设计混合充氧装置,净化水体。利用厌氧池、缺氧池等装置,实现水体循环再生利用。实验结果表明:所提方法净化处理6周后,水体中氨氮、硝酸盐氮、总氮、总磷去除率分别为95.6%、74.4%、88.5%和91.3%,符合廊道湿地水体治理要求。

集输油用非金属柔性复合管研制与性能评价

针对油气田地面集输管线腐蚀泄露、结蜡堵塞问题,研究开发了一种高性能油气介质相容性好、内压强度高的非金属柔性复合管,并对制备的非金属柔性复合管内衬层进行油品介质相容性试验以及相关力学性能评价。结果表明,在温度70℃、压力10 MPa、0号柴油介质下浸泡1080 h后,内衬管氧化诱导时间(OIT)衰减率为14.3%,远小于普通PE100管材的衰减率(56.9%);拉伸强度衰减率为8.01%,低于普通PE100管材(18.05%),具有较好的耐介质相容性。对制备的DN50 mm非金属柔性复合管进行评价,爆破压力可达37.2 MPa,在最小弯曲半径600 mm下,全周期循环弯曲10次未出现开裂,循环后爆破强度为31.2 MPa。通过长期静液压试验预测寿命表明,在40~50℃和使用压力为9.6 MPa工况下,该管材可正常服役50年。产品各项性能完全满足GB/T 38725.2—2020和SY/T 6662.2—2020相关要求,为油气田地面集输道提供了新的选择。

木质基复合相变材料的研究现状与发展趋势

木材作为一种来源广泛、廉价且可再生的生物质多孔材料,其天然的三维分级孔隙网络不仅能够有效地吸附相变材料,而且为相变材料的多功能化应用提供了可能。介绍了相变材料的分类,讨论了各种木质基复合相变材料基本功能强化的方法;综述了木质基复合相变材料在光热转换、磁热转换、显色改良、透明化及超疏水等方向的多元化应用现状。最后指出,对于基体与相变材料之间的相互作用关系、更加绿色高效地提升封装效率方法及材料的实际调温节能应用效果等仍需进一步探究,木质基复合相变材料在电-热储存、红外隐身、农药释放及荧光发射等领域的应用将是未来重要的研究方向。

香菇生长条件及新型栽培基质研究进展

综述了香菇生长所需的碳源、氮源、矿物质和维生素等营养条件及温度、空气、水分、光线和酸碱度等环境因素,概括了竹屑、果木废弃物、中药材渣、农作物肥料等新型栽培基质的研究现状。指出了新型栽培基质在研究、应用及推广中存在应用研究不够深入全面、相应的配套技术研究不到位、相关安全问题研究匮乏等问题,并对其研究与应用的发展前景进行了展望,以期为新型栽培基质的研究利用提供参考,为香菇种植产业的发展提供参考。

活性介质促进纸塑铝复合包材中纸纤维分离回收的研究

探究了水力碎浆过程中材料质量分数、搅拌时间、搅拌速率和温度等因素对纸纤维分离率的影响,并在碎浆体系中引入了表面活性剂、无机盐和无机碱3类活性介质.结果表明,添加活性介质后,纸纤维分离率提高了7.31%~38.80%,长纤维比例提高了11%.其中,表面活性剂十二烷基苯磺酸钠的使用效果最好.

SEEPAGE ABILITY OF HIGH-PRESSURE HOT COMPOSITE FOAM IN POROUS MEDIA

The technology of hot composite foam displacement refers to the injection of high-temperature flue gas and foaming and stabilizing agent into wells with a certain concentration, and after meeting the formation water, a composite foam system is formed in the reservoir. This foam displacement technology involves thermal function and so is related to nitrogen, carbon dioxide and foam flooding characteristics. After analyzing seepage flow law of hot composite foam system, seepage flow experiment of composite foam under high pressure was conducted, and seepage flow ability of hot composite foam in porous media was investigated. In the experiment, surfactant HY-3 was chosen as the foaming agent and hot flue gas was chosen as the foaming gas, and high-pressure hot foaming apparatus was employed in experiments. The experimental results indicate that the surfactant HY-3 could form stable foam in porous media, and the foam has strong ability of plugging. It is concluded that the sealing performance of foam is improved with increasing permeability and resistance coefficient and with incresing injection rate and foam strength. After foam injection, sealing characteristics of heterogeneous cores is better than that of homogeneous cores. The foam pressure has a process of transmission in porous media. In this process, with the increase of injection volume, pressure from the inlet to the outlet increases gradually, which indicates that stable foam has been formed inside the core.

蒸汽驱替稠油水热裂解改质行为的室内物理模拟

以胜利油田某稠油作为研究对象,将岩心作为多孔介质填充在岩心驱替仪中模拟地层条件,采用双亲性催化剂,研究了不同反应条件下稠油水热裂解改质行为。结果表明,在多孔介质条件下,采用直接驱替的方式,稠油降黏率达到20.8%;在多孔介质体系中加入双亲性催化剂后,采用先反应后驱替的方式,稠油黏度显著降低,在低温环境(65℃)下进行驱替的降黏率为57.9%,但在低温环境下驱替导致沥青质组分摩尔质量增大,沥青质摩尔质量由5244 g/mol增加到6690 g/mol。当反应完成后保持高温环境(265℃)时,直接用热水驱替的降黏效果更好,裂解程度更高,其降黏率最高达到96.0%。研究结果对稠油水热裂解反应在现场应用过程中的操作条件优化具有重要的指导意义。