摘要：Fe-containing graphitic carbon nitride（Fe-g-C3N4） materials were synthesized via one-step pyroly-sis of FeCl3 and dicyandiamide. The physicochemical properties of the synthesized Fe-g-C3N4 sam-ples were characterized by N2 adsorption-desorption, X-ray diffraction, thermal gravimetric, Fourier transform infrared, UV-vis diffuse reflectance, X-ray photoelectron spectroscopy, and transmission electron microscopy. The Fe cations were anchored by nitrogen-rich g-C3N4, whereas the graphitic structures of g-C3N4 were retained after the introduction of Fe. As heterogeneous catalysts, Fe-g-C3 N4 exhibited good catalytic activity in the direct hydroxylation of benzene to phenol with H2O2, affording a maximum yield of phenol of up to 17.5%. Compared with other Fe- and V-containing g-C3N4 materials, Fe-g-C3N4 features a more convenient preparation procedure and higher catalytic productivity of phenol.

摘要：In this paper,by combining a second-order sliding mode(SOSM)algorithm with the saturation technique,a novel SOSM control scheme has been *** feature of the proposed SOSM controller lies that there is a saturation function imposed on the sliding variable,which could significantly enlarge the domain of attraction for the closed-loop *** geometric method has been utilized to prove that all the sliding variables will be steered to the origin in a finite ***,the relation between the control parameters and the shape of the phase trajectory has also been ***,the proposed method has been applied to the tracking control problem for a robotic manipulator.

摘要：Heart diseases remain the top threat to human health,and the treatment of heart diseases changes with each passing *** evidence shows that three-dimensional(3D)printing allows for a more precise understanding of the complex anatomy associated with various heart *** addition,3D-printed models of cardiac diseases may serve as effective educational tools and for hands-on simulation of surgical *** introduce examples of the clinical applications of different types of 3D printing based on specific cases and clinical application scenarios of 3D printing in treating heart *** also discuss the limitations and clinically unmet needs of 3D printing in this context.

摘要：为实现煤矿井下孤岛工作面上隅角及采空区瓦斯高效治理,针对其地层应力高、地质条件复杂(夹矸层多、煤质松软、裂隙发育)、定向钻进难以成孔等特点,在山西某矿进行了大孔径煤层透巷定向钻孔全孔下筛管工艺的应用研究。试验设计4个定向钻孔,完成4个定向钻孔,孔径φ153 mm、孔深276~279 m、轨迹上下偏差≤0.8 m、左右偏差≤1.8 m、φ89 mm钢制筛管下深276.2~280.0 m,钻孔末端分别封孔2.4、2.1、2.7、2.8 m,各项参数均达到设计要求。试验结果为孤岛工作面瓦斯治理开辟了新思路,为其他类型透巷钻孔末端封孔处理提供了成功经验。

摘要：随着全球化石能源逐渐枯竭和温室效应加剧,人们赖以生存的自然环境遭到了严重破坏,如何开发新能源或高效的能源转换装置已经成为当前的研究热点.质子交换膜燃料电池(PEMFCs)作为高效的能源转换装置可以通过电化学反应将氢气(H2)中储存的化学能直接转化为电能,具有零排放、零污染、转化效率高等优点,其商业化发展能够有效地缓解当前的能源与环境危机.由于工作温度差异,PEMFCs分为低温质子交换膜燃料电池(LTPEMFCs)和高温质子交换膜燃料电池(HT-PEMFCs).贵金属铂(Pt)是PEMFCs中最常用的催化剂材料之一,然而Pt的抗毒化能力相对较弱,导致其催化剂稳定性较差.此外,Pt的低利用率、高成本,进一步限制了其大规模商业化应用.PEMFCs燃料中存在微量的杂质气体(尤其是一氧化碳(CO)),CO在反应过程中会吸附在催化剂表面而不容易去除,导致Pt催化剂表面活性位点被毒化.除了CO的毒化作用,HT-PEMFCs催化层界面由于磷酸(PA)的随机分布也会引起Pt催化剂的毒化问题,进一步导致催化剂的活性降低.因此,开发高效抗毒化Pt基催化剂并探究其抗毒化机制是推动PEMFCs发展的关键.本文系统地阐述了PEMFCs中Pt基催化剂的毒化问题,重点讨论Pt基催化剂的设计、合成及其抗毒化机制;最后,对PEMFCs中Pt基催化剂的发展与挑战进行探讨和展望.

摘要：With the increasing of complexity of complex mechatronic products, it is necessary to involve multidis- ciplinary design teams, thus, the traditional customer requirements modeling for a single discipline team becomes difficult to be applied in a multidisciplinary team and project since team members with various disciplinary backgrounds may have different interpretations of the customers＇ requirements. A new synthesized multidisci- plinary customer requirements modeling method is pro- vided for obtaining and describing the common understanding of customer requirements （CRs） and more importantly transferring them into a detailed and accurate product design specifications （PDS） to interact with dif- ferent team members effectively. A case study of designing a high speed train verifies the rationality and feasibility of the proposed multidisciplinary requirement modeling method for complex mechatronic product development. This proposed research offersthe instruction to realize the customer-driven personalized customization of complex mechatronic product.

摘要：声爆问题是制约超声速客机商业运营的重要因素之一。为抑制声爆,湾流公司提出了安装于机头的静音锥方案,取得了一定的效果。但静音锥方案也存在一定的不足,主要体现在难以配平以及作动机构复杂的问题。针对此问题提出了一种改进的圆滑过渡静音锥方案,并使用基于雷诺平均(RANS)方程的CFD求解器HUNS3D和基于Thomas波形参数法的远场FL-BOOM声爆传播程序,验证了所提方案对于抑制超声速飞机声爆的有效性,并就静音锥的多项特征对其降低声爆效果的机理进行了分析,证明了影响多级静音锥降爆效果的主要因素是长度而不是级数,但长度增加对低声爆效果也有利。研究结果对超声速飞机静音锥设计具有重要的参考价值。

摘要：OBJECTIVE: To investigate the effects of warming moxibustion Tianshu(ST 25, bilateral) and Qihai(CV6) in patients with diarrhea-dominant irritable bowel syndrome(D-IBS) by assessing predominant factors, and determining the best factor combinations and their interactions. To identify the optimal quantity of warming moxibustion Tianshu(ST 25, bilateral) and Qihai(CV 6) to achieve optimal ***: An L9(3~4) orthogonal design was applied to 233 confirmed subjects based on the three most influential factors and the three most frequently used levels. Nine programs were *** were assigned to four subgroups according to age and gender; each subject underwent one of the nine programs randomly. We selected Tianshu(ST 25, bilateral) and Qihai(CV 6). The scores of symptoms and the IBS Quality of Life(IBS-QOL) were evaluated after the final ***: After treatment, clinical symptoms of all patients were significantly improved(P = 0.001).Quality of life also improved significantly(P < 0.05).For all the participants, frequency was the dominating factor regarding symptoms(P = 0.01). Duration was the dominating factor for quality of life(P =0.0001). The best combination for improving symptoms in 30-40-year-old male and female patients was two courses of 10 min each once a day, and for41-50-year-old male and female patients it was three courses of 10 min(males) or 30 min(females)twice a day. The best combination for quality of life was three courses of 20 min once a day. No interaction was found between frequency and course, or frequency and ***: Warming moxibustion Tianshu(ST25, bilateral) and Qihai(CV 6) is a promising therapy for D-IBS. To acquire optimal efficacy, the three main factors(duration, frequency and treatment course) of the warming moxibustion should reach a specific quantity and be combined appropriately.

摘要：为解决煤矿井下地质探查上斜钻孔带压封堵异常区时,漏浆、跑浆及加压管磨损破裂等问题,设计出带有锥形头、单向阀和内置导流管的改进型止浆塞,并在山西某矿进行了现场试验。试验对7个钻孔下入孔底止浆塞,均达到设计下入深度,平均下深191 m,平均膨胀压力5.1 MPa,合格率100%,下入过程中未出现加压管磨损或断裂事故。对孔内有毒有害气体含量偏高的2^(#)、6^(#)、7^(#)钻孔进行持续观测,发现在下入止浆塞后,孔口有毒有害气体含量均呈不同程度衰减趋势,其中H_(2)S气体含量分别衰减40%、33%、13%;CO气体含量分别衰减20%、70%、25%;CH_(4)气体含量分别衰减0.3%、4.4%、10%。试验结果表明,改进型止浆塞结构设计合理,能够按要求下入指定孔深,且封堵效果良好,孔内有毒有害气体得到有效隔绝,保证了巷道掘进及采面回采安全高效进行。

摘要：通过动态等效转动惯量分析,讨论了扭转减振器的减振频带特性与局域共振声子晶体带隙的相似性。基于局域共振声子晶体理论提出扭转减振器减振带隙的计算方法,并研究了扭转减振器几何设计参数及材料设计参数对减振带隙的影响规律。在此基础上,针对某国产MPV车型传动系扭转振动引致的车内轰鸣声问题,运用减振带隙计算方法设计扭转减振器,试制、安装样件并进行整车传动系扭振及车内噪声试验。结果表明,该扭转减振器可有效抑制传动系扭转振动,降低车内轰鸣声,提升整车声振舒适性。