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CdSe/Cu core/shell nanowires (NWs) are successfully synthesized by a wet chemical method for the first time. By utilizing the solution-liquid-solid (SLS) mechanism, CdSe NWs are fabricated by Bi seeds, which act as catalysts. In the subsequent radial overcoating of the Cu shell on the CdSe NWs, Fe ions have been proven to be an indispensable and efficient catalyzer. The thickness of the Cu shell could be well controlled in the range of 3 to 6 nm by varying the growth temperature (from 300 to 360 °C). Our synthetic strategy pioneers a new possibility for the controlled synthesis of semiconductor-metal heterostructure NWs (especially for II-VI semiconductors), such as CdS/Cu, ZnS/Au, and ZnO/Ag, which had broad application prospects in photoconductors, thin-film transistors, and light-emitting diodes. Theoretically, electrons flow from a higher Fermi-level material to the bottom Fermi-level at the metal-semiconductor heterojunction interface, which aligns the Fermi level and establishes the Schottky barrier. It leads to excess negative charges in metals and excess positive charges in semiconductors. Therefore, those effective electron traps reduce the probability of photogenerated electron-hole pair recombination efficiently, which has been widely applied in solar cells, sensors, photocatalysis, and energy storage. The breakthrough and innovation of this synthesis method have opened up a new synthetic route with a mild reaction environment, low energy consumption, and convenience.

CuInxGa1−xSe2 (CIGS) nanowires were synthesized for the first time through an in situ cation exchange reaction by using CuInSe2 (CIS) nanowires as a template material and Ga-OLA complexes as the Ga source. These CIGS nanowires maintain nearly the same morphology as CIS nanowires, and the Ga/In ratio can be controlled through adjusting the concentration of Ga-OLA complexes. The characteristics of adjustable band gap and highly effective light-absorbances have been achieved for these CIGS nanowires. The light-absorbing layer in photovoltaic devices (PVs) can be assembled by employing CIGS nanowires as a solar-energy material for enhancing the photovoltaic response. The highest power conversion efficiency of solar thin film semiconductors is more than 20%, achieved by the Cu(InxGa1−x)Se2 (CIGS) thin-film solar cells. Therefore, these CIGS nanowires have a great potential to be utilized as light absorber materials for high efficiency single nanowire solar cells and to generate bulk heterojunction devices.

Axial nanowire heterostructures composed of cadmium sulfide (CdS)/copper indium diselenide (CuInSe2) and copper indium telluride (CuInTe2)/copper indium diselenide (CuInSe2) were synthesized by a solution-liquid-solid (SLS) method with the catalyzer of bismuth nanocrystals. Electron microscopy and diffraction studies show CuInTe2 and CuInSe2 segments growing along the [112] direction with a clear epitaxial interface between them. In CdS/CuInSe2 nanorod heterostructures, CuInSe2 and CdS segments grow along the [112] and [111] direction, respectively, with an obvious epitaxial interface between them. Energy-dispersive X-ray spectrometry demonstrates the alloy-free composition modulation in two nanorod heterostructures. In CuInTe2/CuInSe2 nanorod heterostructures, Te and Se are localized in CuInTe2 and CuInSe2 segments, respectively. Cu/In/Se and Cd/S are localized in the CuInSe2 and CdS sections of the CdS/CuInSe2 nanorod heterostructures. This research confirms that the SLS mechanism provides a general alternate technique to prepare multicomponent axial 1D heterostructures that have been difficult to generate by using either catalyst-free solution-phase synthesis or vapor-liquid-solid growth.

Ternary CuInTe2 and quaternary CuInSexTe2–x nanowires were successfully synthesized for the first time by a solution–liquid–solid (SLS) mechanism. Crystalline, straight, and nearly stoichiometric CuInTe2 and CuInSexTe2–x nanowires were readily achieved by using the molecular precursors and in the presence of molten Bi nanoparticles and coordinating capping ligands. The temperature and reactant order-of-addition of this reaction strongly affected the composition of the reaction product and the morphology obtained. These CuInTe2 and CuInSexTe2–x nanowires are outstanding light absorbers from the near-IR through the visible and ultraviolet spectral regions and, thereby, comprise new soluble and machinable “building blocks” for applications in solar-light utilization.

Morphology plays a decisive role in the properties of nanomaterials. In this paper, foreign metal ions have been proved to be an effective morphology controller for solution–liquid–solid (SLS) reaction. Multipod and branched II–VI semiconductor nanowires are formed in the presence of foreign metal ions. On the basis of the advantage of SLS mechanism, we explore Bi-seeded CdSe/CdS multipod heterojuntions and demonstrate their potential to produce more sophisticated and multicomponent nanomaterials.

Magnetic flux leakage (MFL) detection is one of the most popular methods of pipeline inspection. It is a nondestructive testing technique which uses magnetic sensitive sensors to detect the magnetic leakage field of defects on both the internal and external surfaces of pipelines. This paper introduces the main principles, measurement and processing of MFL data. As the key point of a quantitative analysis of MFL detection, the identification of the leakage magnetic signal is also discussed. In addition, the advantages and disadvantages of different identification methods are analyzed. Then the paper briefly introduces the expert systems used. At the end of this paper, future developments in pipeline MFL detection are predicted.

We report on the synthesis of CuInTe2 nanoparticles and their function in photovoltaic equipment, such as solar cells. Under certain synthesis conditions, the CuInTe2 nanocrystals form shape with nanocrystals, nanorods or nanocubes. It was found that CuTe nanocrystals could be converted to CuInTe2 by addition of an In reactant. CuInTe2 nanorods were synthesized using this method.

Oil and gas transportation in pipeline plays an important role in the lifeline of national economy, industrial production and daily life. In China, aging phenomenon of oil and natural gas pipeline is widespread in the existing pipeline. Therefore, the safety of the pipeline has been concerned. It is a great significance for forecasting dent depth of transportation pipeline accurately. In this paper, according to the complicated radial displacement and the characteristic of RBF neural network, the model of RBF neural was constructed combining with pipeline dent depth data pipeline. The RBF model was applied to predict dent depth in the pipelines, it was testified that the RBF neural network model has higher prediction accuracy than BP neural network model.

Mass energy loss happens in the air supply through large-scale complex pneumatic pipeline grid, and it widely exists in various kinds of manufacturing enterprises. In this paper, to improve efficiency and safety of compressed air grid system, a "smart pneumatic pipeline grid" is introduced. Furthermore, based on the supply and demand characteristics of key nodes of smart pneumatic pipeline grid, an energy-saving supply strategy of smart pneumatic pipeline grid was proposed. Moreover, to test the energy-saving supply strategy of the smart pneumatic pipeline network, a typical smart pneumatic pipeline grid was studied. In this study, the feasibility of the energy-saving supply strategy can be verified through a typical smart pneumatic pipeline grid. This paper provides an intelligent energy-saving technology of the compressed air system.