Dynamic yard crane dispatching in container terminals with predicted vehicle arrival information

The performance of a container terminal depends on many aspects of operations. This paper focuses on the optimal sequencing of a yard crane (or YC for short) for serving a fleet of vehicles for delivery and pickup jobs. The objective is to minimize the average vehicle waiting time. While heuristic algorithms could not guarantee an optimal solution, a conventional mathematical formulation such as mixed integer program would require too much computing time. We present two new algorithms to efficiently compute YC dispatching sequences that are provably optimal within the planning window. The first algorithm is based on the well-known A^∗ search along with an admissible heuristics. We also incorporate this heuristics into a second backtracking algorithm which uses a prioritized search order to accelerate the computation. Experimental results show that both new algorithms perform very well for realistic YC jobs. Specifically, both are able to find within seconds optimal solutions for heavy workload scenarios with over 2.4 × 10¹⁸ possible dispatching sequences. Moreover, even when the vehicle arrival times are not accurately forecasted, the new algorithms are still robust enough to produce optimal or near-optimal sequences, and they consistently outperform all the other algorithms evaluated.     

Leaching of additives from construction materials to urban storm water runoff

Urban water management requires further clarification about pollutants in storm water. Little is known about the release of organic additives used in construction materials and the impact of these compounds to storm water runoff. We investigated sources and pathways of additives used in construction materials, i.e., biocides in facades' render as well as root protection products in bitumen membranes for rooftops. Under wet-weather conditions, the concentrations of diuron, terbutryn, carbendazim, irgarol 1051 (all from facades) and mecoprop in storm water and receiving water exceeded the predicted no-effect concentrations values and the Swiss water quality standard of 0.1 microg/L. Under laboratory conditions maximum concentrations of additives were in the range of a few milligrams and a few hundred micrograms per litre in runoff of facades and bitumen membranes. Runoff from aged materials shows approximately one to two orders of magnitude lower concentrations. Concentrations decreased also during individual runoff events. In storm water and receiving water the occurrence of additives did not follow the typical first flush model. This can be explained by the release lasting over the time of rainfall and the complexity of the drainage network. Beside the amounts used, the impact of construction materials containing hazardous additives on water quality is related clearly to the age of the buildings and the separated sewer network. The development of improved products regarding release of hazardous additives is the most efficient way of reducing the pollutant load from construction materials in storm water runoff.     

正交试验法在环己烷羧酸亚硝化反应中的应用

采用正交设计试验法对甲苯法己内酰胺生产工艺中的环己烷羧酸亚硝化反应进行了研究 ,考察了反应温度、时间、配比和三氧化硫浓度等因素对反应的转化率、选择性以及副产物的影响 ,获得了最佳的反应条件为温度 73℃ ,时间 15min ,环己烷羧酸与亚硝基硫酸的质量比 2 .4,体系中三氧化硫质量含量 8%。     

Synthesis, Characterization of Ag/MCM-41 and the Catalytic Performance for Liquid-phase Oxidation of Cyclohexane

Nano-scale silver supported mesoporous molecular sieve Ag/MCM-41 was directly prepared by one-pot synthesis method. The prepared sample was characterized by XRD, TEM, and N₂ sorption. The results showed that the sample of Ag/MCM-41 had no appreciable incorporation of silver into the mesoporous matrix of MCM-41 with good crystallinity, and silver nanoparticles were dispersed inside or outside of the channels in the mesoporous host. The catalytic performance of the sample for the cyclohexane liquid-phase oxidation into cyclohexanone and cyclohexanol by oxygen in the absence of solvents without inducing agents was investigated. The 83.4% selectivity to cyclohexanol and cyclohexanone at 10.7% conversion of cyclohexane was obtained over Ag/MCM-41 catalyst at 428 K for 3 h. The turn over numbers (TONs) of Ag/MCM-41 was up to 2946. The catalytic activity of Ag/MCM-41 was also compared with Ag/TS-1 as well as Ag/Al₂O₃. The results indicated that Ag/MCM-41 showed superior activity to both Ag/TS-1 and Ag/Al₂O₃. A calcined Ag/MCM-41 was found to be an efficient catalyst for the cyclohexane oxidation into cyclohexanol and cyclohexanone using oxygen as oxidant.     

Frequency domain lifetime and spectral imaging microscopy

In the femtoliter observation volume of a two-photon microscope, multiple fluorophores can be present and complex photophysics can take place. Combined detection of the fluorescence emission spectra and lifetimes can provide deeper insight into specimen properties than these two imaging modalities taken separately. Therefore, we have developed a detection scheme based on a frequency-modulated multichannel photomultiplier, which measures simultaneously the spectrum and the lifetime of the emitted fluorescence. Experimentally, the efficiency of the frequency domain lifetime measurement was compared to a time domain set-up. The performance of this spectrally and lifetime-resolved microscope was evaluated on reference specimens and living cells labeled with three different stains targeting the membrane, the mitochondria, and the nucleus.     

腈纶散纤湿料装缸染色法

腈纶散纤在干料装染色加工过程中易结块,易产生色花,针对这一问题,中提出了湿料装缸染色法,通过小样实验和小大生产实践,有效地解决了以上问题。     

Stability Assessment of Virgin Coconut Oil‐Based Emulsion Products

In recent years, there has been dramatic growth in the market for virgin coconut oil (VCO). VCO, a promising functional food oil, has gained popularity and captured public attention worldwide. Two VCO‐based emulsion products were developed as a new nutritional food supplement with the aim of increasing the consumption of VCO. The stability of VCO‐based emulsion products was assessed during a storage period of 3 months to gauge the quality of the optimized VCO‐based emulsions. The particle‐size distributions of the VCO‐based emulsions remained stable throughout the 3‐month storage period at 25 and at 50°C. However, a slight increase in the particle sizes was observed in the VCO‐based emulsions samples after 2 months of storage at 4 °C. Nevertheless, phase separation did not occur in either of the VCO‐based emulsions products throughout the storage‐stability assessment period. No signs of microbial growth were detected in the emulsion products during the storage period. Furthermore, no significant changes in the free fatty acid contents of the emulsion products were observed during storage at 4 or 25°C throughout the storage period. The VCO‐based emulsion products possessed sufficient emulsion stability to withstand changes at different storage temperatures.     

硫酸二甲酯副反应对甲胺磷含量的影响

本文通过分析硫酸二甲酯发生的副反应对甲胺磷含量的影响，提出了抑制副反应、提高甲胺磷含量的有效途径。     

风口前理论燃烧温度在安钢高炉上的应用

在当前高炉高冶强、高喷煤比、低焦比、低硅冶炼的情况下,对影响高炉稳定顺行、高产低耗的参数进行分析,掌握其中的规律,通过对合理的风口前理论燃烧温度认识和控制,使高炉在强化冶炼操作下,达到高产、优质、低耗、长寿的目的。     

五氯苯甲腈的合成

以苯甲腈和氯气为原料,用气固催化氯化法研制了五氯苯甲腈。考察了催化剂、反应温度、原料配比等因素对产品纯度的影响,其收率达９０％以上,产品纯度９９％。