A note on two-machine no-wait flow shop scheduling with deteriorating jobs and machine availability constraints

This paper is concerned with two-machine no-wait flow shop scheduling problems in which the actual processing time of each job is a proportional function of its starting time and each machine may have non-availability intervals. The objective is to minimize the makespan. We assume that the non-availability intervals are imposed on only one machine. Moreover, the number of non-availability intervals, the start time and end time of each interval are known in advance. We show that the problem with a single non-availability interval is NP-hard in the ordinary sense and the problem with an arbitrary number of non-availability intervals is NP-hard in the strong sense.     

Analysis of dislocation nucleation from a crystal surface based on the Peierls-Nabarro dislocation model

Dislocation nucleation from a stressed crystal surface is analyzed based on the Peierls-Nabarro dislocation model. The variational boundary integral approach is used to obtain the profiles of the embryonic dislocations in various three-dimensional nucleation configurations. The stress-dependent activation energies required to activate dislocations from their stable to unstable saddle point configurations are determined. Compared to previous analyses of this type of problem based on continuum elastic dislocation theory, the present analysis eliminates the uncertain core cutoff parameter by allowing for the existence of an extended dislocation core as the embryonic dislocation evolves. Moreover, atomic information can be incorporated to reveal the dependence of the nucleation process on the profile of the atomic interlayer potential as compared to continuum elastic dislocation theory in which only elastic constants and Burgers vector are relevant. Finally, the presented methodology can also be readily used to study dislocation nucleation from the surface heterogeneities such as cracks, steps, and quantum structures of electronic devices.     

A Chemically Soldered Polyoxometalate Single-Molecule Transistor

Polyoxometalates have been proposed in the literature as nanoelectronic components, where they could offer key advantages with their structural versatility and rich electrochemistry. Apart from a few studies on their ensemble behaviour (as monolayers or thin films), this potential remains largely unexplored. We synthesised a pyridyl-capped Anderson–Evans polyoxometalate and used it to fabricate single-molecule junctions, using the organic termini to chemically “solder” a single cluster to two nanoelectrodes. Operating the device in an electrochemical environment allowed us to probe charge transport through different oxidation states of the polyoxometalate, and we report here an efficient three-state transistor behaviour. Conductance data fits a quantum tunnelling mechanism with different charge-transport probabilities through different charge states. Our results show the promise of polyoxometalates in nanoelectronics and give an insight on their single-entity electrochemical behaviour.     

Two birds,one stone: host-guest complex of indocyanine green–β-cyclodextrin for fundus angiography

Journal of Inclusion Phenomena and Macrocyclic Chemistry - Indocyanine green (ICG) angiography is of great importance for ophthalmic diagnostic applications and is mainly used to check for...     

Rescheduling problems with deteriorating jobs under disruptions

In this paper, we consider two single-machine rescheduling problems with linear deteriorating jobs under disruption. By a deteriorating jobs, we mean that the actual processing time of the job is an increasing function of its starting time. The two problems correspond to two different increasing linear function. Rescheduling means a set of original jobs has already been scheduled to minimize some classical objective, then a new set of jobs arrives and creates a disruption. We consider the rescheduling problem to minimize the total completion time under a limit of the disruption from the original scheduling. For each problem, we consider two versions. For each version, the polynomial algorithms are proposed, respectively.     

高效液相色谱法测定盐酸倍他司汀片的有关物质

采用Kromasil C18分析柱,水-乙腈(体积比为68：32)混合液为流动相,流速为1．0ml/min,检测波长为261nm,用高效液相色谱法测定盐酸倍他司汀片的有关物质。盐酸倍他司汀样品溶液中有关物质的色谱峰面积之和及2％盐酸倍他司汀线性对照溶液中主成分的色谱峰面积均与盐酸倍他司汀的浓度线性相关,相关系数分别为0．9991、0.9997。     

On‐chip protein isoelectric focusing using a photoimmobilized pH gradient†

An immobilized pH gradient was directly constructed on the inner wall of a microfluidic chip channel by photoimmobilizing focused carrier ampholytes onto the wall. A mixture of carbonic anhydrase, myoglobin, and trypsin inhibitor was successfully isoelectric‐focused and separated with good linearity between the pI values of proteins and the location of the focused bands. Furthermore, coating methods for the resistance of protein nonselective adsorption and simultaneously for pH gradient photocoupling were screened. The PEG‐silane coating method was found to be better than the cross‐linked polyacrylamide coating and aminosilane modification methods. Finally, based on the open tubular column mode of carrier ampholytes’ immobilization and effective antiadsorption coating, the immobilized pH gradient was reused and the chip was recycled for the first time. By virtue of its remarkable features including simplicity, convenience, high efficiency of protein enrichment and separation, and potential for coupling site‐selective IEF with other analytical or separation techniques, this novel method promises to be useful in several applications related with zwitterionic biomolecules.     

Comparative study of electroless copper deposition based on the seed layers of Pd, PtPd and AuPd

The article reports on electroless deposition of copper films onto p-silicon (1 0 0) using different seed (co-seed) layers of Pd, PtPd and AuPd. The dependence of the compositions and morphologies of different seed layers on resultant Cu films were comparatively studied in detail by atomic force microscopy (AFM), field emission scanning electron microscope (FE-SEM) and X-ray photoelectron spectroscopy (XPS). The activities of electroless copper deposition on the p-silicon (1 0 0) with different seed (co-seed) layers were evaluated by polarization curve. It is concluded that the bimetallic AuPd seed displayed the highest catalytic activity for electroless copper deposition, and followed by the order of PtPd > Pd.     

氮掺杂石墨烯与g-C3N4二维异质体对纳米Fe2O3光催化剂的复合改性

使用相分离的水解-溶剂热法制备了α-Fe₂O₃纳米粒子, 通过简单的湿化学法实现了质量分数为3%的石墨烯、 氮掺杂石墨烯和g-C₃N₄ 3种二维异质体对纳米α-Fe₂O₃的复合改性, 并比较了3种二维异质体对α-Fe₂O₃光催化活性的影响. 结果表明, 在光催化还原二氧化碳和降解液相苯酚过程中, 二维异质体的复合均提高了纳米α-Fe₂O₃的光催化活性, 氮掺杂石墨烯对α-Fe₂O₃的改性效果优于石墨烯, 其中g-C₃N₄对α-Fe₂O₃的改性效果最优. 通过表面光电压谱、 光电化学及羟基自由基等测试, 确认二维异质体的复合改性主要通过促进纳米α-Fe₂O₃的光生电荷分离和提高活性中间组分(羟基自由基)的含量提高纳米α-Fe₂O₃的光催化活性.