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941.
In this study, two novel crystal materials pcp1 and pcp1‐L have been synthesized successfully. The different conformations of the two crystals are mainly attributed to the introduction of the Schiff‐base ligand L ( L =(E)‐4‐methyl‐N‐((6‐methoxypyridin‐2‐yl)methylene)aniline). Subsequently, pcp1 and pcp1‐L composites have been firstly produced by a vacuum filtration method on various substrates (i.e., melamine foam, plastic mesh, carbon fiber cloth and glass cloth). The obtained robust composites show excellent performance in removing PMs owing to high ζ potential, microporous structure, large conjugation system and electron cloud‐exposed metal center (DFT calculations) of pcp1 and pcp1‐L . Particularly, pcp1‐L @glass cloth with low pressure drop exhibits high thermal stability and high long‐term reproducibility. Additionally, the high removal efficiency of pcp1‐L @glass cloth towards particulate matters could also be maintained, even achieving >99.9 % in the car exhaust gas field test.  相似文献   
942.
论文针对钢铁企业炼钢工序具有高温、高能耗、复杂工况的实际特征,从中提炼出生产批调度问题,其工件根据其实际工艺属性可分为多个簇,基于给定的工件簇,决策工件的分批和调度情况,综合考虑工件之间的切换费用,以及工件提前、拖期所导致的惩罚,使得总的生产成本期望最小化,从而降低生产成本;针对该问题,考虑工件的处理时间、工件的加工属性具有不确定性,基于仿真优化思想,建立数学模型,并基于大数定理,对模型目标函数进行近似;提出基于样本近似方法的求解框架,通过随机抽样的方法获得不同规模的样本,针对不同规模的样本,提出Filter & Fan算法对问题进行求解;最后,通过基于实际数据的计算实验验证所提算法的有效性。  相似文献   
943.
944.
945.
For indoor air purification, long-term operation of the air purifier induces the growth of germs and the proliferation of molds, and results in the performance degradation of the air filter. Non-thermal plasma technology could be an effective countermeasure against these problems. Ozone generated by the electric discharge has significant germicidal power and does not produce secondary residual contaminants. Electrostatic force can enable the air filter to function as an electric precipitator. In this study, a non-thermal plasma reactor with wire-wire type electrodes and an air filter is investigated experimentally to improve the performance of the used air filter.  相似文献   
946.
We theoretically investigate plasmonic properties of a calcium film in a Kretschmann excitation scheme. Based on surface plasmon polaritons, the absorbance of the calcium film can be as high as 100% for the p-polarization, much higher than the absorbance for the s-polarization at the wavelength of 422.7 nm, correspondingly to the g Fraunhofer line. The 45 nm thick film of calcium has a high reflectance of about 76% at 422.7 nm for s-polarization. But for p-polarization, there is a minimum in the reflectivity curves at the angle of 19°. The narrow-band filter based on calcium film is particularly suited for working with conventional calcium atomic filter and on-chip integration due to its solid-state bulky feature. Furthermore, the plasmonic filter based on the calcium film is described that may offers new applications in angle- and polarization-sensitive sensor and the detection of weak laser light.  相似文献   
947.
A concurrent multiscale method of coupling atomistic and continuum models is presented in the two-dimensional system. The atomistic region is governed by molecular dynamics while the continuum region is represented by construct- ing the mass and stiffness matrix dependent on the coarsening of the grids, which ensures that they merge seamlessly. The low-pass phonon filter embedded in the handshaking region is utilized to effectively eliminate the spurious reflection of high-frequency phonons, while keeping the low-frequency phonons transparent. These schemes are demonstrated by numerically calculating the reflection and transmission coefficient, and by the further application of dynamic crack propa- gation subjected to mode-I tensile loading.  相似文献   
948.
Dealing with a moving target causes a motion effect (i.e. blurring) on the acquired images. This factor is an important source of measurement uncertainty while exploiting the Digital Image Correlation (DIC) technique. Therefore, the present study aims to evaluate and improve DIC uncertainty in dynamic conditions in the case of translating target. The study focuses on 2D DIC. In the case of 3D DIC similar problems arise, and therefore a complete understanding of two dimensional conditions will be of great help for further studies which deal with 3D conditions. The whole work can be divided into two main parts. In the first part, two different methods to simulate the motion effect on a reference image are proposed, discussed and validated. These methods allow simulating the acquired images in a real dynamic test and estimating the measurement uncertainty caused by the motion effect. The validation is performed by conducting several harmonic vibration tests with an electromagnetic shaker. In the second part of the study a numerical technique is proposed to estimate the motion effect present in an acquired image. This technique gives two main advantages. First of all, since the motion effect itself has a known influence on the uncertainty of measurement (first part of the study), we can predict the DIC׳s uncertainty by just having an acquired image. Furthermore, this numerical technique is used in the last part of this work to improve the performances of DIC in dynamic applications. In this way the bias error and the uncertainty of measurements were considerably decreased.  相似文献   
949.
Zhi‐zi‐chi decoction (ZZCD) is a classical formula widely used in Chinese clinical application. In the present study, a novel and efficient strategy has been developed for screening and identification of multiple constituents and their metabolites of ZZCD using ultra‐high‐performance liquid chromatography combined with triple time‐of‐flight mass spectrometry. The novel approach of an online data acquisition method dependent on multiple mass defect filter and dynamic background subtraction is combined with multiple data processing techniques. First, a total of 109 potential bioactive compounds were detected in ZZCD. Based on the same instrumental conditions, 100 compounds were found in rat biofluids after oral administration of ZZCD, including 61 original compounds of ZZCD as well as 39 metabolites. Conjugations with sulfate, glucuronate and amino acids were found as the predominant metabolic reaction of ZZCD. As more xenobiotics were detected in urine than those in bile were, it demonstrated that multiple components of ZZCD have undergone comprehensive renal excretion. This study reported the urinary and biliary excretion in rats after oral administration of ZZCD for the first time. The present study expands our knowledge about the constituents and metabolism of ZZCD, which could be very useful for further pharmacological and clinical studies of ZZCD.  相似文献   
950.
Four kinds of currently available Nd:hosted laser passive Q-switch and mode-locking modulators: plastic dye sheet, LiF:F2 color center crystal, Cr+4 :YAG crystal and RG1000 colored glass filter were investigated in detail and summarized for comparison for the first time. The LiF:F2 crystal with outstanding annealability, long lifetime, low cost and operability at high repetition rates is highly recommended.  相似文献   
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