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Aiming at the coordination and scheduling problem between Automated Straddle Carrier (Automated Straddle Carrier) and Quay Crane (QC) in automated container terminals, consider that the quay crane cannot cross the straddle carrier, and the straddle carrier and the quay crane cannot be in adjacent lanes at the same time. A mixed-integer optimization model with the objective function of minimizing the final completion time of the quay crane is established under the constraints of different operating speeds and different speeds of straddle carriers in different states. A genetic algorithm based on reinforcement learning is designed, and the initial population is generated by the Q-learning algorithm, and the genetic algorithm (GA) is iterated to increase the diversity of the initial population. Finally, taking 5 groups of experiments as examples, the model is compared and solved by GAMS solver, genetic algorithm and genetic algorithm based on reinforcement learning. The results of an example show that the genetic algorithm based on reinforcement learning can solve the model and make the value of the objective function smaller, thus verifying the feasibility of the modified algorithm.

In order to effectively reduce the cost of empty container dispatching and transportation, an integer programming model for empty container dispatching and transportation with multiple periods and multiple ports was established, and the empty container dispatching and transportation scheme was optimized under the (D, U) inventory control strategy considering the service level. The results show that compared with no inventory control strategy, the (D, U) strategy can effectively reduce the total operating cost of liner companies. Select the service level for sensitivity analysis, and verify that (D, U) control strategy can effectively reduce the dependence of liner companies on container chartering.

Aiming at the joint scheduling problem of AGV and shore bridge in automatic container terminal, considering the waiting and power exchange process of AGV, a mixed integer programming model with the goal of minimizing the final completion time of AGV is constructed. The model considers the changes of buffer area, AGV power and the power consumption differences of AGV in light load, heavy load and waiting state. Genetic algorithm (GA) is used to solve it. Finally, through the analysis of different scale examples, the optimal allocation of shore bridges, the number of AGVs and the AGV power exchange threshold are obtained, so as to reduce the waiting time and the overall completion time.

The brittle feature of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is the major challenge that strongly restricts its application at present. Successfully synthesized bio-based engineering polyester elastomers (BEPE) were combined with PHBV to create entirely bio-composites with the intention of toughening PHBV. Herein, the 2,2-Bis(hydroxymethyl)-propionic acid (DMPA) was grafted onto microcrystalline cellulose (MCC) and then further transformed into hyperbranched polyester structure via polycondensation. The modified MCC, named MCHBP, had plenty of terminal hydroxyl groups, which get dispersed between PHBV and BEPE. Besides, a large number of terminal hydroxyl groups of MCHBP can interact with the carbonyl groups of PHBV or BEPE in a wide range of hydrogen bonds, and subsequently increase the adhesion and stress transfer between the PHBV and BEPE. The tensile toughness and the elongation at break of the PHBV/BEPE composites with 0.5phr MCHBP were improved by 559.7% and 221.8% in comparison to those of PHBV/BEPE composites. Results also showed that MCHBP can play a heterogeneous nucleation effect on the crystallization of PHBV. Therefore, this research can address the current issue of biopolymers' weak mechanical qualities and may have uses in food packaging.

Handrail height and knee joint support both significantly influence sit-to-stand (STS) movement. However, research on the associations between handrail height, knee joint support, and their cumulative effect on STS kinematics and changes in plantar pressure distribution during STS under different handrail heights and knee joint support is still unclear. The main objective of this study was to examine the influence of handrail height and knee joint support on the kinematics and the distribution of plantar pressure in healthy adults during STS. Twenty-six healthy adult subjects aged 23 to 58 years participated in this experiment. The subjects carried out STS movement experiments under 7 conditions: 6 experimental conditions of 3 different heights of handrail, with and without knee joint support, and 1 control condition of standing up naturally. The motions of the markers were recorded using cameras operating at 60 Hz, and total movement time, the percentage of movement time of each phase, trunk tilt angle, joint angle, plantar pressure, and the time from hindfoot to forefoot peak pressure were analyzed and compared. Handrail height significantly influences the percentage of movement time at phase I (P = .015) and the maximum trunk tilt angle (P .05), knee joint support significantly influences the maximum trunk tilt angle and ankle angle (P = .033), and handrail height and knee joint support have an interaction on the time from hindfoot to forefoot peak pressure (P .001). Subjects' STS performance was improved with the use of assistant devices but showed particular improvement under the condition of with knee joint support when the handrail height was middle handrail.

Polypropylene carbonate (PPC)/polybutylene succinate (PBS) blends were prepared by melt-blending with terminal epoxy-based hyperbranched polymers (EHBP) as modifier. The thermal properties, mechanical properties, rheological properties and fracture morphology were characterized by dynamic thermomechanical analyzer (DMA), thermogravimetric analyzer (TGA), electronic universal testing machine, rotating rheometer and scanning electron microscope (SEM). Upon addition of EHBP, the difference between the glass transition temperature of PPC and PBS became smaller, indicating the compatibility of PPC and PBS were improved by EHBP. Furthermore, by adding 0.5phr of EHBP, the impact strength increased from 9.55 to 17.31 kJ/m2, the elongation at break increased from 136.29 to 204.39%, and the tensile strength increased from 10.00 to 16.84 MPa. The fracture surface of the PPC/PBS blends became rough with the increase of EHBP, even with large filamentous structures and tiny holes, which further demonstrated that EHBP acted as an excellent toughening effect on PPC/PBS. Gel content analysis confirmed that both physical and chemical micro-crosslinking were formed after incorporation of EHBP.

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a type of promising bio-based thermoplastic for food packaging but find restricted industrial applications due to its brittleness and poor processability that is caused by its large spherulite sizes. In this study, for the purpose of toughening PHBV, bio-based engineering polyester elastomers (BEPE) were synthesized and blended with PHBV to prepare fully bio-based blends. In order to improve the compatibility and toughness of the BEPE/PHBV blends, epoxy-terminated hyperbranched polyesters (EHBP) were synthesized, which could be homogeneously dispersed into the PHBV/BEPE blends and improve the compatibility between the two phases of the matrix. The results showed that compared to those of the PHBV/BEPE blends, the elongation at break, impact strength and tensile toughness of the PHBV/BEPE blends with 3.0phr EHBP were enhanced by 134.2 %, 76.8 %, and 123.5 %, respectively. The crystallization study demonstrated the crystallization rate of PHBV/BEPE blends decreased due to the addition of EHBP. The reasons lied in that the addition of EHBP leads to chemical cross-linking between PHBV and BEPE. Meanwhile, the formation of hydrogen bonding, co-crystallization and chain entanglement increased the adhesion between PHBV and BEΡE, which generated the superior toughness of the blends.

Surface hydroxylation is the basis for material removal in chemical mechanical polishing (CMP) of monocrystalline silicon, diamond, and YAG crystals. Existing studies use experimental observations to investigate surface hydroxylation, but lack in-depth understanding of the hydroxylation process. In this paper, for the first time to the best of our knowledge, we analyze the surface hydroxylation process of YAG crystals in an aqueous solution using first-principle calculations. The presence of surface hydroxylation was verified by X-ray photoelectron spectroscopy (XPS) and thermogravimetric mass spectrometry (TGA-MS) detections. This study complements the existing research on the material removal mechanism of the CMP process of YAG crystals and provides theoretical support for the future improvement of the CMP technology.

In 2009, a violent murder occurred. Two victims, a 47-year-old mother and her 21-year-old daughter, were murdered at home. After importing the 20 autosomal STR loci and 27 Y-STR loci into a database, no hit had been found. In 2019, a person with a prior criminal record was matched in the national forensic Y-STR database. When increasing the number of detected Y-STR loci to 60, all loci of the bloodstain donor at the crime and the suspect were still found to be identical. With the combined calculation of multiple autosomal STR and kinship index, we were able to identify the perpetrator as a previously unknown illegitimate child of a large family and solved the case.

The hydrogen consumption in refineries is rapidly growing because more sour and heavy crude oils are being processed to produce more transportation fuels and meet increasing market demands. A hydrogen network integration (HNI) strategy including two mathematical models (M1 and M2) is built to reduce the hydrogen consumption and the total cost based on the sulfur compound removal (SCR) kinetics and a fluid catalytic cracker (FCC). M1 is an operational optimization model integrated the SCR kinetics and an FCC to reduce the hydrogen consumption by optimizing the degrees of impurity removal and operating conditions of hydrotreating units. M2 is an HNI model to optimize the hydrogen network structure based on the results from M1. The case study shows that the HNI without kinetics and FCC only reduces by 19.1% and 32.6% in total annualized cost (TAC) and hydrogen consumption. While in the hydrogen network optimization with SCR kinetics and FCC, the reductions of the hydrogen consumption and TAC have reached to 47.9% and 37.1%, which are also more than the reductions of 44.5% and 34.4% in the optimization with lumped kinetics and FCC. Therefore, it is imperative to integrate the SCR kinetics and an FCC in a hydrogen network optimization.

This study facilitates the synthesis process of a novel graft copolymer (flocculant) using carboxymethyl cellulose, acrylonitrile and N-vinyl formamide as raw materials. The carboxymethyl cellulose graft polyamidine (CMC-g-PAMD) can be used as new flocculant to replace the traditional polyacrylamide flocculant, which manifested its excellent flocculation and degradation efficiency. A five-membered cyclic copolymer was prepared by the graft copolymerization, and the synthesized flocculants were characterized by EA, TG-DTG, FT-IR, SEM and NMR, confirming the successful synthesis of the desired copolymers. The operation conditions for copolymerization were experimentally investigated, and the results indicated that the optimal initiator dosage, copolymerization temperature, amidinization temperature, acidification time and flocculant dosage were 4 g/L, 50°C, 90°C, 3 h and 60 mg/L, respectively. Compared with the traditional polyacrylamide flocculant, the CMC-g-PAMD presented an outstanding flocculation ability of 96.1% under its optimal operation conditions, which showed an enormous potential in the application of coalmine waste-water treatment.

In this article, ZIF-8 nanoparticles were synthesized in water and directly added to a polyethyleneglycol (PEG) aqueous solution (water-based mixing process) to prepare ZIF-8/PEG mixed matrix membranes (MMMs) for pervaporation desulfurization. The structure and properties of ZIF-8 particles were characterized by Fourier Transform-Infrared Spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and BET analysis. The surface composition and structural morphology of all ZIF-8/PEG MMMs were systematically investigated by FT-IR and SEM. The effect of ZIF-8 content on the pervaporation performance of ZIF-8/PEG membranes was investigated. Versus pure PEG membranes, both the total flux and the sulfur enrichment factor of the ZIF-8/PEG MMMs were remarkably increased. This phenomenon is attributed to the good compatibility between PEG and ZIF-8 particles and the high thiophene selective sorption of ZIF-8 particles (confirmed by molecular simulation). Optimal pervaporation performance was achieved at a 4 wt% loading of ZIF-8 particles with the flux of 1.96 kg/(m2 h) and the sulfur enrichment factor of 8.93. These increased by 397.46% and 18.75% versus pristine PEG membrane, respectively. In addition, the effect of operation temperature and feed sulfur content on membrane performance were also systematically investigated.

In this paper, we investigate the Tomas–Stein restriction estimates on convex cocompact hyperbolic manifolds $\Gamma \backslash{\mathbb{H}}^{n+1}$. Via the spectral measure of the Laplacian, we prove that the Tomas–Stein restriction estimate holds when the limit set has Hausdorff dimension $\delta _\Gamma

A series of oxides (La2 − xCexCoO4 ± y) with perovskite-like structure were prepared by the Pechini sol–gel method for dry reforming of methane reaction (DRM). The prepared catalysts were characterized by BET, XRD, TGA, H2-TPR and SEM. Experimental results indicate that the addition of Ce can impact both sample morphology and catalytic performance significantly compared with La2CoO4 catalyst, and LaCeCoO4 presented the highest catalytic ability among all the samples. The Ce addition tends to increase the specific surface area of La2 − xCexCoO4 ± y from 0.2 to 8.5 m2·g− 1, suggesting that LaCeCoO4 catalyst contained more well-dispersed active sites and more space to reaction. Moreover, the catalytic performance and anti-coking ability were substantially improved after Ce addition during DRM, which may be attributed to the decrease of LaCoO3 particle size and growth of oxygen storage capacity, respectively.

A metal + nonmetal (Mg + N) partial cosubstitution method for improving the dehydrogenation properties of lithium borohydride (LiBH4), which is a potential solid hydrogen storage material, is propo...

Polypropylene carbonate (PPC)/polybutylene succinate (PBS) blends were prepared by melt-blending with terminal epoxy-based hyperbranched polymers (EHBP) as modifier. The thermal properties, mechanical properties, rheological properties and fracture morphology were characterized by dynamic thermomechanical analyzer (DMA), thermogravimetric analyzer (TGA), electronic universal testing machine, rotating rheometer and scanning electron microscope (SEM), etc. Upon addition of EHBP, the difference between the glass transition temperature of PPC and PBS became smaller, indicating the compatibility of PPC and PBS were improved by EHBP. Furthermore, by adding 0.5phr of EHBP, the impact strength increased from 9.55 kJ/m− 2 to 17.31 kJ/m− 2, the elongation at break increased from 136.29–204.39%, and the tensile strength increased from 10.00 MPa to 16.84 MPa. The fracture surface of the PPC/PBS blends became rough with the increase of EHBP, even with large filamentous structures and tiny holes, which further demonstrated that EHBP acted as an excellent toughening effect on PPC/PBS. Gel content analysis confirmed that both physical and chemical micro-crosslinking were formed after incorporation of EHBP.

Surface defects deteriorate the performance of optical crystals and semiconductor crystals. Chemical mechanical polishing technology is one of the most effective methods to smooth surfaces and meanwhile to reduce surface defects like cracks, pits and scratches. However, it was found that scratches still remain on some crystal surfaces even after chemical mechanical polishing. Various crystals such as Si, YAG, Lu 2 O 3 and Al 2 O 3 were polished with silicasol with the particle diameter of 80 nm, and the surfaces morphologies were measured by AFM. The surfaces of Si and YAG crystals are covered with sub-nanometer depth scratches, while there are atomic step structures formed on the surfaces of Lu 2 O 3 and Al 2 O 3 crystals. To reveal the underlying mechanism of the formation of sub-nanometer depth scratches, the interactions between particles and crystal surfaces during CMP are studied through Hertz theory and First-principle calculation. It is found that the appearance of such scratches is closely related to the properties of atomic structure.