论工程爆破专业人员必备的科技基础

由原水电部建设总局委托水利水电爆破咨询服务部和武汉水利电力学院承办的爆破专业专科班已经毕业了。该班的学制为两年半,学员系通过成人高考择优录取的在职人员。在两年半的学习期间应当开设哪些课程才能培养     

两座钢筋混凝土单曲拱桥的控制爆破拆除

介绍了两座钢筋混凝土单曲拱桥的控制爆破拆除工艺.此两座桥均与新建的高速公路大桥相邻,要求拆除旧桥的上部结构.详细论述了两座钢筋混凝土单曲拱桥爆破拆除方案的选择、爆破参数的确定及安全防护措施.     

城区台阶爆破工程的飞石控制

在城区进行小台阶爆破,必须把爆破飞石控制在一定的范围之内。为此,根据爆破破岩理论和现场调研,分析了飞石产生的原因,讨论了飞石的类型。以两个实际爆破工程为例,介绍了针对具体情况所采取的飞石防范措施。实践证明,只要措施得当,飞石是可以控制的。     

城区台阶爆破工程的飞石控制

在城区进行小台阶爆破,必须把爆破飞石控制在一定的范围之内。为此,根据爆破破岩理论和现场调研,分析了飞石产生的原因,讨论了飞石的类型。以两个实际爆破工程为例,介绍了针对具体情况所采取的飞石防范措施。实践证明,只要措施得当,飞石是可以控制的。     

150m高钢筋混凝土烟囱控制爆破拆除

采用两段两次控制爆破拆除了150m高钢筋混凝土烟囱。通过选用复式梯形爆破缺口和合理的爆破参数,并采用开挖减振沟及铺设缓冲垫层等安全防护措施,使烟囱爆破达到了定向准确、安全、破碎好的效果,可为类似爆破工程提供参考。     

沙溪口水电站二期上游混凝土围堰拆除爆破

介绍了采用塑料导爆管接力式起爆网络的顺序微差控制爆破新技术,分两次成功地拆除了沙溪口水电站二期上游混凝土围堰工程。爆破混凝土量19800m~3,总装药量为15.84t,起爆段数分别为227段和345段。爆破完全达到了预期的效果。爆破安全监测结果也表明,爆破对邻近的水工建筑物没有产生丝毫不利影响。     

15Om高钢筋混凝土烟囱控制爆破拆除

采用两段两次控制爆破拆除了150m高钢筋混凝土烟囱.通过选用复式梯形爆破缺口和合理的爆破参数,并采用开挖减振沟及铺设缓冲垫层等安全防护措施,使烟囱爆破达到了定向准确、安全、破碎好的效果,可为类似爆破工程提供参考.     

150m高钢筋混凝土烟囱控制爆破拆除

采用两段两次控制爆破拆除了150m高钢筋混凝土烟囱。通过选用复式梯形爆破缺口和合理的爆破参数,并采用开挖减振沟及铺设缓冲垫层等安全防护措施,使烟囱爆破达到了定向准确、安全、破碎好的效果,可为类似爆破工程提供参考。     

30m高砖烟囱单向折叠爆破拆除

介绍了复杂条件下的砖烟囱单向折叠爆破拆除。阐述了在倾倒空间不足情况下,为保证烟囱准确倾倒,确定了两段不同段高,单向折叠爆破的技术方案。同时介绍了爆破方案的选择和爆破切口的设计,通过两切口的起爆时差,减弱上下两节烟囱的相互影响,并结合爆破网路设计和有效的安全防护措施,较好地实现了爆破拆除。     

密平路石方路堑开挖控制爆破

采用了浅孔和中深孔爆破相结合的台阶开挖方法。按照谨慎爆破方法确定合理的爆破参数。应用孔内和排间微差起爆方式控制爆破震动。为确保边坡的稳定 ,采用了光面爆破技术以及V形延时起爆和路堑中央炮孔先起爆的两种起爆顺序。根据具体的地形条件 ,选择或创造合适的最小抵抗线方向 ,避免飞石的危害。     

卷烟包装“水雾”与“磨花”问题研究

目的针对卷烟条盒商标纸出现的"水雾"和"磨花"等问题,从商标纸、薄膜、美容器等方面找出改进和解决措施。方法对商标纸、薄膜、美容器等3个因素进行三因素四水平的正交试验,寻找影响卷烟条盒包装耐水雾和耐磨花的因素。结果通过正交试验确定了影响条盒包装耐磨花的主次因素依次为美容器、薄膜、商标纸;影响包装耐水雾的主次因素依次为美容器、商标纸、薄膜;从薄膜方面解决"磨花"和"水雾"问题时,改进方向主要是改进其耐摩擦性能,并适当提高雾度;从商标纸方面解决"磨花"和"水雾"问题时,改进方向主要是进行油墨和光油的选择,干燥功率和速度等的优化,并适当提高摩擦因数;从美容器方面解决"磨花"和"水雾"问题时,首先考虑将美容器升级为活动结构,并适当降低温度。结论薄膜、商标纸对耐磨花指数、耐水雾指数有不同程度的影响,但仅当美容器升级为YTCJ-R2活动全自动装置美容器时,磨花现象得到明显改善,水雾现象基本解决,其对薄膜、条盒商标纸材料亦有较强的适应性。     

Producing "self-plasticizing" ion-selective membranes

Polymer membranes have been explored for the analysis of ions that do not require plasticizers and with photocurable properties. This work was focused on investigating the viability of the methacrylic-acrylic copolymers as new self-plasticizing membrane matrixes for ion-selective electrodes or other ion-sensor applications. Copolymers with glass transition temperatures ranging from -20 to -44 degrees C could be prepared without added plasticizer and were found to be functional as ion-selective membranes. Both free-radical solution polymerization and photopolymerization could be used, and "self-plasticizing" behavior of copolymers was observed with a high alkylacrylate (R = C4) content. This was found to be compatible with most commercially available ionophores, and sensors for potassium, sodium, calcium and pH were fabricated entirely by photocure procedures; single-step procedures for the immobilization of benzo-15-crown-5 ionophore on these self-plasticizing copolymer matrixes were also developed. Even though the ionophore was immobilized, potentiometric studies revealed that the ionophore remained functional, and thus, these copolymers have the advantage of suffering neither leaching of ionophore nor plasticizers. All these sensors exhibited a Nernstian or near Nernstian response with selectivity comparable to plasticized PVC membranes or other plasticized and photocurable polymer membranes. The long-term response of the potassium sensor with immobilized ionophore and the sodium sensor showed little deterioration for as long as one month and three months, respectively, under continuous use.     

N-bike折叠自行车的设计研究

 为了使折叠自行车既骑行舒适又易携带,对车架、链盒等主要部件进行受力分析及优化设计.设计出的N-bike自行车,经过5次完成折叠,体积为0.03 m³,质量为5.4 kg,车架为“N”字型形状,根据人机工程学原理设计,布局合理.N-bike骑行更舒适,传动更省力,实用性强,外形动感时尚,更适合作为城市便捷的代步工具．     

TRIAXIAL ANALYSIS OF THE "POKER-CHIP" TEST

Axial compression of thin circular discs made of plasticized epoxy resin was studied. The plane faces were cemented to platens rigid compared with the material of the discs so that the constraint due to cementing created in the discs a three-dimensional state of stress. The internal strain distribution was measured by the moiré method which yielded enough data for an evaluation of this state of stress. The influence of the aspect-ratio of diameter D to thickness t of the disc was investigated.     

“行为-力”同步可视化展示系统的开发

动物行为信号的同步可视化展示为分析和理解动物的运动行为特征提供了有效手段。为了便于直观分析人的运动姿态与脚底接触力的关系,搭建了“行为-力”同步可视化展示系统。首先,利用LabVIEW软件实现了基于UDP （user datagram protocol,用户数据报协议） 的多通道三维力传感器和Kinect相机的信号采集;其次,提出了一种基于插值的数据同步处理方法,实现了运动姿态信号与脚底受力信号的同步处理;然后,采用多线程技术构建了同步实时可视化的虚拟展示系统,实现了运动轨迹、运动姿态和脚底接触力的同步实时展示;最后,通过实验验证了该展示系统具有较好的实时性。研究结果表明,“行为-力”同步可视化展示系统是研究动物运动行为特征的有效装置。     

Observations on "orthogonality" in comprehensive two-dimensional separations

The concept and definition of orthogonality in the context of comprehensive two-dimensional (2D) separations are interesting topics of active discussion. Over the years, several approaches have been taken to quantify the degree of orthogonality, primarily to serve as a metric to optimize (and compare) comprehensive 2D separations. Recently, a mathematical function was reported that is qualitatively instructive for the purpose of providing such a metric. However, the mathematical function has some quantitative shortcomings. Herein, we both explore and partially correct this function. The orthogonality metric, referred to previously and herein as the orthogonality, O, was mathematically related to the fraction of the 2D separation space occupied by compounds (i.e., fractional coverage) and the peak capacity, P, for one dimension of the 2D separation. The fractional coverage, f, is simply related to the percentage coverage, which is equal to 100%(f). Our main finding was that the values for O as a function of P for a given percentage coverage achieve a constant value at large P but deviate severely to lower O values at small P. For comprehensive 2D separations operated such that the second dimension is at small P, the findings we report have consequences for those who consider applying the O metric. Finally, it is discussed that the percentage coverage may be a better metric to gauge the extent to which the compounds in a given sample mixture have been disseminated in the 2D separation space.     

Carbohydrate-protein interactions by "clicked" carbohydrate self-assembled monolayers

A Huisgen 1,3-dipolar cycloaddition "click chemistry" was employed to immobilize azido sugars (mannose, lactose, alpha-Gal) to fabricate carbohydrate self-assembled monolayers (SAMs) on gold. This fabrication was based on preformed SAM templates incorporated with alkyne terminal groups, which could further anchor the azido sugars to form well-packed, stable, and rigid sugar SAMs. The clicked mannose, lactose, and alpha-Gal trisaccharide SAMs were used in the analysis of specific carbohydrate-protein interactions (i.e., mannose-Con A; ECL-lactose, alpha-Gal-anti-Gal). The apparent affinity constant of Con A binding to mannose was (8.7 +/- 2.8) x 10(5) and (3.9 +/- 0.2) x 10(6) M(-1) measured by QCM and SPR, respectively. The apparent affinity constants of lactose binding with ECL and alpha-Gal binding with polyclonal anti-Gal antibody were determined to be (4.6 +/- 2.4) x 10(6) and (6.7 +/- 3.3) x 10(6) M(-1), respectively by QCM. SPR, QCM, AFM, and electrochemistry studies confirmed that the carbohydrate SAM sensors maintained the specificity to their corresponding lectins and nonspecific adsorption on the clicked carbohydrate surface was negligible. This study showed that the clicked carbohydrate SAMs in concert with nonlabel QCM or SPR offered a potent platform for high-throughput characterization of carbohydrate-protein interactions. Such a combination should complement other methods such as ITC and ELISA in a favorable manner and provide insightful knowledge for the corresponding complex glycobiological processes.     

“离位”增韧预成型体压缩特性

针对"离位"增韧预成型体的液态成型工艺性,研究了两种不同结构形式增韧层"离位"增韧预成型体的厚度压缩特性。分别采用多孔薄膜结构增韧层、高孔隙率无纺布结构增韧层与碳纤维织物交替铺层制备"离位"增韧预成型体,采用力学试验机测试其厚度压缩特性。实验结果表明,预成型体压缩过程中,在相同压力水平下,增韧层的引入会降低预成型体的纤维体积分数;不同压力水平下,预成型体的压缩行为与增韧层结构形式有关。此外,采用织物预成型体厚度压缩本构模型,对"离位"增韧预成型体的压缩厚度进行了预测,通过模型预测值与实验值的比较,确定了模型中的经验指数k=2时,两者吻合较好。     

Quantitative analysis of convective dose in hemofiltration and hemodiafiltration: "predilution" vs. "postdilution" reinfusion

In hemofiltration (HF) and hemodiafiltration (HDF), removal of medium and high-molecular-weight solutes is greatly enhanced by convective mechanisms as compared with simple diffusion; increasing convective flows may allow greater removal rates of these solutes. Use of "predilution" (pre-H[D]F) may allow higher ultrafiltration rates than the "postdilution" mode (post-H[D]F); yet, the dilution of plasma water may have unpredictable effects on "endogenous" water convection. We have applied a mathematical analysis to evaluate and compare endogenous water convective flow rates in pre-H(D)F vs. post-H(D)F. Endogenous plasma water recovered in ultrafiltrate was calculated according to patient (hematocrit, total protein level) and session parameters (blood flow, ultrafiltration rate, programmed weight loss), in absolute terms and as a fraction of endogenous plasma water delivery to the filter. Maximally efficient post-H(D)F was modelled according to a preset postfilter hematocrit or filtration fraction. Nomograms were constructed expressing endogenous water convective fluxes in relation to parameters of interest (ultrafiltration rate, blood flow, hematocrit) with both post-H(D)F and pre-H(D)F, and "efficiency" of pre-H(D)F vs. post-H(D)F (as the ratio of endogenous water convective flow rate with the 2 techniques) as a function of the ultrafiltration/reinfusion rate. In post-H(D)F, the model predicts maximal ultrafiltration rates within the limits of a preset hemoconcentration at the filter outlet; additionally, the model allows to calculate ultrafiltration/reinfusion quantities to be set in pre-H(D)F to equal and overcome maximal convective efficiency of post-H(D)F. This "equivalence" ultrafiltration rate may greatly vary according to patient's hematocrit and blood flow, so that the ultrafiltrate-reinfusate volume available in the system dictates, in any patient, which mode of reinfusion may attain higher "endogenous" convective flow rates. Pre-H(D)F may allow higher fractional and absolute "endogenous" convective flow rates as compared with post-H(D)F, provided that adequate amounts of reinfusate are available. For lower reinfusate volumes than "equivalence" values, post-H(D)F remains a better option.     

Mass spectrometry "sensor" for in vivo acetylcholine monitoring

Developing sensors for in vivo chemical monitoring is a daunting challenge. An alternative approach is to couple sampling methods with online analytical techniques; however, such approaches are generally hampered by lower temporal resolution and slow analysis. In this work, microdialysis sampling was coupled with segmented flow electrospray ionization mass spectrometry (ESI-MS) to perform in vivo chemical monitoring. The use of segmented flow to prevent Taylor dispersion of collected zones and rapid analysis with direct ESI-MS allowed 5 s temporal resolution to be achieved. The MS "sensor" was applied to monitor acetylcholine in the brain of live rats. The detection limit of 5 nM was sufficient to monitor basal acetylcholine as well as dynamic changes elicited by microinjection of neostigmine, an inhibitor of acetycholinesterase, that evoked rapid increases in acetycholine and tetrodotoxin, a blocker of Na(+) channels, that lowered the acetylcholine concentration. The versatility of the sensor was demonstrated by simultaneously monitoring metabolites and infused drugs.