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1.
The aim of this paper is to study the laser-induced backside wet cleaning techniques for glass substrates. Two kinds of laser cleaning techniques are proposed in this study. The first involves applying an Nd:YAG laser to the backside of the substrate which is submerged in water. A metal plate is placed below the glass substrate. Most of the laser energy will be absorbed by the metal plate. The metal then vaporizes the water and generates a turbulent bubble flow. The bubble flow removes the alumina particles from the surface of the glass substrate. The second involves using a CO2 laser to generate turbulent bubble flow to remove the particles. Both methods were successfully demonstrated for the removal of submicron particles of 0.5 μm in size. The phenomena of bubble generation and diffusion are presented in the paper. Because the laser is applied to the backside of the substrate, the damage due to the laser heat can be significantly reduced. The quality and efficient of the backside processing is better than those of the front side processing. The proposed techniques have great potential to provide an improved solution for glass cleaning.  相似文献   
2.
In this study, we describe the preparation and characterization of a new class of thermoset hybrid networks containing aliphatic polyester and polyhedral oligomeric silsesquioxanes (POSS). The copper‐free 1,3‐dipolar cycloaddition click reaction of internal alkyne functionalized aliphatic polyester and multifunctional azido POSS with different concentrations led to highly crosslinked thermoset networks. The click reactions performed under ambient conditions (i.e., in tetrahydrofuran at room temperature for 1 day) in the absence of any catalyst. The chemical composition of hybrid networks and homogenous distribution of POSS molecules were confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy with energy dispersive spectroscopy. The swelling ratios of hybrid networks were commonly decreased by increasing POSS‐N3 content and by changing polar solvents to apolar solvents. Thermogravimetric analysis results demonstrated that the thermal stability of hybrid networks increased with higher POSS feeding ratio. Tensile tests were applied to evaluate the mechanical properties of hybrid networks. Compared to neat aliphatic polyester, the mechanical properties of hybrid networks significantly improved. For instance, the tensile strength were enhanced from 5 MPa to 19 MPa by increasing the concentration of azido functionalized POSS from 10 to 40. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2222–2227  相似文献   
3.
The supply chain literature analyzing supplier–retailer contracts and channel coordination has typically focused on profit or revenue maximization as the members’ sole objective. In such settings, it is well known that a simple wholesale price contract is not effective in coordinating the channel due to double marginalization. Recently, Cui et al. [Cui, T.H., Raju, J.S., Zhang, Z.J., 2007. Fairness and channel coordination. Management Science 53 (8) 1303–1314] introduced the members’ fairness concerns into channel coordination. Assuming a linear demand function, the authors show that a coordinating wholesale price contract can be designed when only the retailer or both parties are concerned about fairness. In this paper, we extend the authors’ results to other nonlinear demand functions that are commonly used in the literature. Our analysis reveals that, compared to the linear demand, the exponential demand function requires less stringent conditions to achieve coordination when only the retailer is fairness-concerned.  相似文献   
4.
Chalcones targeting neurodegenerative diseases have been known as attractive structures in drug design and discovery. In this study, phenothiazine-based chalcones as ChEs and MAOs inhibitors were designed and synthesized via base-catalyzed Claisen-Schmidt condensation, and chemical structures of the compounds were elucidated by NMRs and HRMS. Compounds 3 and 9 showed promising inhibition potency against AChE enzyme with IC50 values of 0.221 μM and 0.053 μM while compound 9 displayed remarkable inhibition potency toward MAO-B enzyme with IC50 value of 0.048 μM. Compound 9 , as a dual-target inhibitor, selectively inhibited AChE and MAO-B enzymes. This promising behavior is an advantage for the compound since MAO-B and AChE inhibition have a role in Alzheimer's disease. Fused tricyclic ring systems such as phenothiazine incorporated with chalcone moiety being multitargeting ligands may help scientists for the rational design of novel lead compounds targeting neurodegenerative illnesses.  相似文献   
5.
Promotions are important tools for matching supply and demand in many industries. In the United States automotive industry, promotions are frequently offered, which may be given directly to customers (rebates) or given to dealers (incentives) to stimulate demand. We analyze the performance of customer rebate and retailer incentive promotions under competition. We study a setting with two manufacturers making simultaneous pricing and promotion decisions, and with two price-discriminating retailers as Stackelberg followers making simultaneous order quantity decisions. In the benchmark case with no promotions, we characterize the equilibria in closed form. We find that retailer incentives can be used by manufacturers to simultaneously improve each of their profits but can potentially lead to lower retailer profits. When manufacturers use customer rebates, we show that a manufacturer is able to decrease the profit of her competitor while increasing her own profit, although she is also at risk for her competitor to use rebates in a similar fashion. Unlike the monopoly case where the manufacturers are always better off with retailer incentives, customer rebates can be more profitable under some cases in the presence of competition. Using numerical examples we generate insights on the manufacturers’ preference of promotions in different market settings.  相似文献   
6.
Multicellular biology is dependent on the control of cell–cell interactions. These concepts have begun to be exploited for engineering of cell-based therapies. Herein, we detail the use of a multivalent lipidated scaffold for the rapid and reversible manipulation of cell–cell interactions. Chemically self-assembled nanorings (CSANs) are formed via the oligomerization of bivalent dihydrofolate reductase (DHFR2) fusion proteins using a chemical dimerizer, bis-methotrexate. With targeting proteins fused onto the DHFR2 monomers, the CSANs can target specific cellular antigens. Here, anti-EGFR or anti-EpCAM fibronectin-DHFR2 monomers incorporating a CAAX-box sequence were enzymatically prenylated, then assembled into the corresponding CSANs. Both farnesylated and geranylgeranylated CSANs efficiently modified the cell surface of lymphocytes and remained bound to the cell surface with a half-life of >3 days. Co-localization studies revealed a preference for the prenylated nanorings to associate with lipid rafts. The presence of antigen targeting elements in these bifunctional constructs enabled them to specifically interact with target cells while treatment with trimethoprim resulted in rapid CSAN disassembly and termination of the cell–cell interactions. Hence, we were able to determine that activated PBMCs modified with the prenylated CSANs caused irreversible selective cytotoxicity toward EGFR-expressing cells within 2 hours without direct engagement of CD3. The ability to disassemble these nanostructures in a temporally controlled manner provides a unique platform for studying cell–cell interactions and T cell-mediated cytotoxicity. Overall, antigen-targeted prenylated CSANs provide a general approach for the regulation of specific cell–cell interactions and will be valuable for a plethora of fundamental and therapeutic applications.

Multicellular biology is dependent on the control of cell-cell interactions. The prenylated antigen-targeted CSANs provide a general approach for the regulation of specific cell-cell interactions and will be valuable for a plethora of fundamental and therapeutic applications.  相似文献   
7.
8.
We introduce a spatial coordinate transformation technique to compress the excessive white space (i.e. free-space) in the computational domain of finite methods. This approach is based on the form-invariance property of Maxwell’s equations under coordinate transformations. Clearly, Maxwell’s equations are still satisfied inside the transformed space, but the medium turns into an anisotropic medium whose constitutive parameters are determined by the coordinate transformation. The proposed technique can be employed to reduce the number of unknowns especially in high-frequency applications wherein a finite method requires an electrically-large computational domain. After developing the analytical background of this technique, we report some numerical results for finite element simulations of electromagnetic scattering problems.  相似文献   
9.
Novel efficient chiral tetraoxacalix[2]arene[2]triazine-based organocatalysts have been designed and synthesized from the reaction of tetraoxacalix[2]arene[2]triazine with R/S-phenylethylamine or R/S-1-naphthylethylamine for the Aldol reaction of acetone with aromatic aldehydes to furnish the Aldol adducts in 71–92% yields with excellent enantioselectivities (78–99%).  相似文献   
10.
In the numerical solution of some boundary value problems by the finite element method (FEM), the unbounded domain must be truncated by an artificial absorbing boundary or layer to have a bounded computational domain. The perfectly matched layer (PML) approach is based on the truncation of the computational domain by a reflectionless artificial layer which absorbs outgoing waves regardless of their frequency and angle of incidence. In this paper, we present the near-field numerical performance analysis of our new PML approach, which we call as locally-conformal PML, using Monte Carlo simulations. The locally-conformal PML method is an easily implementable conformal PML implementation, to the problem of mesh truncation in the FEM. The most distinguished feature of the method is its simplicity and flexibility to design conformal PMLs over challenging geometries, especially those with curvature discontinuities, in a straightforward way without using artificial absorbers. The method is based on a special complex coordinate transformation which is ‘locally-defined’ for each point inside the PML region. The method can be implemented in an existing FEM software by just replacing the nodal coordinates inside the PML region by their complex counterparts obtained via complex coordinate transformation. We first introduce the analytical derivation of the locally-conformal PML method for the FEM solution of the two-dimensional scalar Helmholtz equation arising in the mathematical modeling of various steady-state (or, time-harmonic) wave phenomena. Then, we carry out its numerical performance analysis by means of some Monte Carlo simulations which consider both the problem of constructing the two-dimensional Green’s function, and some specific cases of electromagnetic scattering.  相似文献   
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