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In comparison with lithium-ion batteries (LIBs) with liquid electrolytes, all-solid-state lithium batteries (ASSLBs) have been considered as promising systems for future energy storage due to their safety and high energy density. As the pivotal component used in ASSLBs, composite solid polymer electrolytes (CSPEs), derived from the incorporation of inorganic fillers into solid polymer electrolytes (SPEs), exhibit higher ionic conductivity, better mechanical strength, and superior thermal/electrochemical stability compared to the single-component SPEs, which can significantly promote the electrochemical performance of ASSLBs. Herein, the recent advances of CSPEs applied in ASSLBs are presented. The effects of the category, morphology and concentration of inorganic fillers on the ionic conductivity, mechanical strength, electrochemical window, interfacial stability and possible Li+ transfer mechanism of CSPEs will be systematically discussed. Finally, the challenges and perspectives are proposed for the future development of high-performance CSPEs and ASSLBs.

Mesoporous TiO2 spheres with high crystallinity and large specific surface area were facilely prepared via sol–gel and solvothermal methods. By tuning the time and temperature of the solvothermal process, the specific surface area and pore size of TiO2 spheres were fine-controlled without any additives. Compared with the dye-sensitized solar cell (DSC) based on the commercial P25 nanoparticles, the dye-sensitized solar cell employing optimized TiO2 spheres achieves an excellent efficiency of 10.3%, due to the outstanding dye-loading and light-scattering abilities as well as attenuated charge recombination. Furthermore, an impressive efficiency of 11.2% can be obtained after TiCl4 post-treatment. More importantly, in combination with a single-layer TiO2 film composed of mesoporous spheres and low-volatility electrolyte, the DSC exhibits high efficiency and long-term durability.

A novel photoelectrochemical self-powered ultraviolet photodetector (UVPD) has been assembled employing Ag@SiO2 core–shell nanoparticles (NPs) incorporated TiO2 nanocubes (NCs) as the photoanode. The incorporation of the plasmonic core–shell NPs can boost the photocurrent of the self-powered UVPD. Finite difference time domain (FDTD) and transient absorption spectroscopy (TAS) were employed to understand plasmonic enhancement processes. By optimizing the incorporated ratio of Ag@SiO2 NPs, the photocurrent of UVPD with 2 wt % Ag@SiO2 NPs reaches the maximum value in view of the enhanced light harvesting and effective inhibition of charge recombination. More importantly, the UVPD with 2 wt % Ag@SiO2 NPs achieves a high on/off ratio of 8212 and a remarkable responsivity of 0.151 A W–1, combined with a rapid response time, prominent spectral selectivity, and photosensitivity linearity response.

Epoxy resin as an insulating material is widely used in superconducting motors because it has excellent insulation properties under extremely low temperature. The insulation properties could be damaged by surface discharge. Our previous studies were focused on surface insulation breakdown behaviors in the room temperature condition, and the results showed that the accumulated heat at the discharge area was the main reason to cause insulation breakdown. The performance of surface discharge erosion resistance in a liquid nitrogen environment was not clear. In this paper, surface insulation breakdown behaviors in liquid nitrogen were studied to clarify the effects of extremely low temperature and BN particles on tracking performance. A digital camera and an infrared camera were used to measure the breakdown process. The camera was used to record the time to breakdown and observe the whole insulation breakdown process, while the thermal accumulation and decay process was measured by the infrared camera. Obtained results indicated that insulation breakdown performance was affected by BN fillers and low temperature significantly. In the liquid nitrogen environment, the time to tracking failure is much longer than that in air. It is concluded that the extremely low temperature in liquid nitrogen could produce an inhibitory effect on surface insulation breakdown.

Heterostructured TiO2/MgO nanowire arrays (NWAs) were grown vertically on fluorine-doped tin oxide (FTO) glass by a simple solvothermal method. A photoelectrochemical self-powered UV photodetector (UVPD) was fabricated using the heterostructured TiO2/MgO nanowire arrays (NWAs) as the photoanode. The TiO2/MgO NWAs based UVPDs shows a higher photocurrent density (J) and open-circuit voltage (Voc) with respect to the UVPD with bare TiO2 NWAs under UV light irradiance. The intrinsic role of the MgO shell layer on the J and Voc varitions of UVPDs is investigated in detail. An impressive responsivity of 0.233 A W−1 was achieved for the UVPD with TiO2/MgO NWAs, which is the highest responsivity for photoelectrochemical self-powered UVPDs based on various TiO2 nanostructured photoanodes so far. Moreover, this UVPD also exhibits a high on/off ratio, fast response time, excellent visible-blind characteristic and linear optical signal response.

A novel self-powered UV photodetector (UVPD) based on the photoelectrochemical cell (PECC) has been constructed using the TiO2 coated SnO2 mesoporous spheres (SnO2-MS@TiO2). This self-powered UVPD displays a higher photocurrent density compared to the UVPD with the pure SnO2-MS. By means of external quantum efficiency (EQE), UV-vis absorption, and electrochemical impedance measurements, we scrutinize the intrinsic role of the TiO2 coating layer on the photocurrent enhancement. Under UV irradiation, this UVPD exhibits a high on/off ratio of 11519, a fast rise time of 0.007 s and decay time of 0.006 s, together with the excellent visible-blind characteristic and linear optical signal response. The self-powered photodetector is a promising candidate for application in high-sensitivity and high-speed UVPDs.

T helper cell is a key component of the immune system. They mediate humoral and cellular immune responses against pathogens and other diseases like cancer by inducing and activating effector cells such as B cells, cytotoxic T cells and innate cells. They are also involved in the regulation of immune responses by controlling the persistence and magnitude of the response. Activation of naïve T cell is initiated by interaction with antigen presenting cells. The downstream signal transduction and the cytokine milieu can lead to their proliferation and differentiation into different T cell subtypes. To facilitate the study of Th2 and Th17 cells, we present a rapid protocol to efficiently induce cytokine associated with Th2 and Th17 cells from total PBMC. Canonical anti-CD3 and anti-CD28 clones are used to activate the purified cells. Different sets of bioassay-validated cytokines, including IL-12, IL-4, IL-6, IL-1β, IL-2, and TGF-β1 are used to induce cytokine associated with Th2 and Th17 cells. Hallmark cytokine and transcription factor expression profile of different lineages are evaluated by Flow Cytometry. In summary, we have successfully developed a rapid protocols to induce cytokine expression in vitro associated with Th2 and Th17 using high quality reagents developed in BioLegend.

Zn-doped SnO2 nanocrystals were successfully synthesized by a simple hydrothermal method. It is found that Zn doping into SnO2 can induce a negative shift in the flat-band potential (VFB) and increase the isoelectric point. As a result, dye-sensitized solar cells (DSCs) based on Zn-doped SnO2 nanocrystal photoanodes exhibit longer electron lifetimes and higher dye loading compared to undoped SnO2 based DSCs. The overall power conversion efficiency (η) of the optimized Zn-doped SnO2 based DSC reaches 4.18% and increases to 7.70% after the TiCl4 treatment. More importantly, a remarkable η of 8.23% is achieved for DSCs based on a high-quality double-layer SnO2 photoanode with the TiCl4 treatment, to the best of our knowledge, which is so far the best reported efficiency for DSCs based on SnO2 photoanodes.

Novel hierarchical SnO2 hollow nanospindles self-assembled from nanorods have been successfully synthesized via a templating approach under hydrothermal conditions. The influence of the reactant concentration on SnO2 products is investigated in detail. It is found that the interplay of the acidic etching of Fe2O3 templates and controlled hydrolysis of SnCl2 is significant for the formation of the hierarchical SnO2 hollow nanostructures. The evolution process and formation mechanism of the hollow structures with nanorods are analyzed from the angle of nucleation and morphology. Moreover, the electrochemical properties of the hollow structures are also studied by charge–discharge cycling, the result displays that the hierarchical SnO2 hollow nanostructure exhibits much better lithium storage properties with higher reversible capacities and enhanced cyclic capacity retention than the commercial SnO2 nanoparticles.

Vertically aligned rutile TiO2 nanowire arrays (NWAs) with lengths of ∼44 μm have been successfully synthesized on transparent, conductive fluorine-doped tin oxide (FTO) glass by a facile one-step solvothermal method. The length and wire-to-wire distance of NWAs can be controlled by adjusting the ethanol content in the reaction solution. By employing optimized rutile TiO2 NWAs for dye-sensitized solar cells (DSCs), a remarkable power conversion efficiency (PCE) of 8.9% is achieved. Moreover, in combination with a light-scattering layer, the performance of a rutile TiO2 NWAs based DSC can be further enhanced, reaching an impressive PCE of 9.6%, which is the highest efficiency for rutile TiO2 NWA based DSCs so far.

Ab-producing plasma cells (PCs) serve as key participants in countering pathogenic challenges as well as being contributors to autoimmune and malignant disorders. Thus far, only a limited number of PC–specific markers have been identified. The characterization of the unique variable lymphocyte receptor (VLR) Abs that are made by evolutionarily distant jawless vertebrates prompted us to investigate whether VLR Abs could detect novel PC antigens that have not been recognized by conventional Abs. Here, we describe a monoclonal lamprey Ab, VLRB MM3, that was raised against primary multiple myeloma cells. VLRB MM3 recognizes a unique epitope of the CD38 ectoenzyme that is present on plasmablasts and PCs from healthy individuals and on most, but not all, multiple myelomas. Binding by the VLRB MM3 Ab coincides with CD38 dimerization and NAD glycohydrolase activity. Our data demonstrate that the lamprey VLRB MM3 Ab is a unique reagent for the identification of plasmablasts and PCs, with potential applications in the diagnosis and therapeutic intervention of PC or autoimmune disorders.

Large-scale uniform bicone-like ZnO microcrystals were successfully synthesized via a simple solution method at lower temperature (80 °C). The as-prepared bicones, composed of two cones, possess a single-crystal hexagonal structure and grow along the [0001] direction. The influence of the reactant concentration on the size and shape of the ZnO samples has been studied in detail, and the results revealed that reactant concentration plays a crucial role in determining the final morphologies of the samples. The growth process of the bicone-like ZnO microcrystals was viewed by field emission scanning electron microscopy (FESEM) characterization, and a possible formation mechanism was proposed. Optical properties of the bicone-like ZnO microcrystals were also investigated by photoluminescence (PL) spectroscopy. The room-temperature PL spectrum of the bicone-like ZnO microcrystals shows a strong UV emission peak. The UV emission is further identified to originate from the radiative free exciton recombination by...

A TCR-like molecule (TCRL) with two canonical ITIM has been identified in the sea lamprey. We show here that TCRL is preferentially expressed by lymphocytes bearing variable lymphocyte receptors. To examine the potential of the TCRL inhibitory motifs, chimeric proteins comprising the FccRIIb extracellular and transmembrane domains and the TCRL intracellular domain were expressed in a mouse B-cell line. BCR co-ligation with the WT version of the FccRIIb/TCRL chimeric protein resulted in its tyrosine phosphorylation and the inhibition of BCR-induced calcium mobilization, whole-cell protein tyrosine phosphorylation and Erk/Akt/JNK activation. Tyrosine to phenylalanine mutations in either or both ITIM compromised the inhibitory capacity of this receptor chimera. Analysis of receptor-associated proteins indicated that the inhibition is mediated by recruitment of the protein tyrosine kinases, SHP1 and SHP2. These findings demonstrate the inhibitory potential of TCRL and its expression by clonally diverse lymphocytes bearing the variable lymphocyte receptors, thereby implying an immunomodulatory role for this ancestral TCR relative in a jawless vertebrate.

It has been speculated that before vertebrates evolved somatic diversity-based adaptive immunity, the germline-encoded diversity of innate immunity may have been more developed. Amphioxus occupies the basal position of the chordate phylum and hence is an important reference to the evolution of vertebrate immunity. Here we report the first comprehensive genomic survey of the immune gene repertoire of the amphioxus Branchiostoma floridae. It has been reported that the purple sea urchin has a vastly expanded innate receptor repertoire not previously seen in other species, which includes 222 toll-like receptors (TLRs), 203 NOD/NALP-like receptors (NLRs), and 218 scavenger receptors (SRs). We discovered that the amphioxus genome contains comparable expansion with 71 TLR gene models, 118 NLR models, and 270 SR models. Amphioxus also expands other receptor-like families, including 1215 C-type lectin models, 240 LRR and IGcam-containing models, 1363 other LRR-containing models, 75 C1q-like models, 98 ficolin-like models, and hundreds of models containing complement-related domains. The expansion is not restricted to receptors but is likely to extend to intermediate signal transducers because there are 58 TIR adapter-like models, 36 TRAF models, 44 initiator caspase models, and 541 death-fold domain-containing models in the genome. Amphioxus also has a sophisticated TNF system and a complicated complement system not previously seen in other invertebrates. Besides the increase of gene number, domain combinations of immune proteins are also increased. Altogether, this survey suggests that the amphioxus, a species without vertebrate-type adaptive immunity, holds extraordinary innate complexity and diversity.

In order to examine the problem of how to improve the use of information technology (IT) in enterprises, this paper makes an exploration from the perspective of organizational absorptive capacity. We propose the concept of IT absorptive capacity from an organizational level. A dynamic process model is developed to further analyze IT absorption. IT absorptive capacity of this process is embodied as six forms: identification, adoption, adaptation, acceptance, infusion, and knowledge management. By means of questionnaire surveys of 76 Chinese enterprises, the main factors that favor or disable the capacity of each stage are discovered. Using the method of system dynamics, a conceptual model of IT absorptive capacity is developed to analyze the action mechanism of the factors in detail. The model indicates that the critical factors are embodied in the aspect of management. Furthermore, it demonstrates that IT absorption is a spiral process, during which IT absorptive capacity evolves dynamically and, consequently, promotes IT use.

Yttrium-doped ZnO thin films were deposited on silica glass substrates by the sol–gel method. The structural, electrical and optical properties of yttrium-doped ZnO thin films were investigated systematically and in detail. All the thin films have a preferred (0 0 2) orientation. When compared with the electrical resistivity values of films without annealing treatment, the values of films annealed in the reducing atmosphere were decreased by about three orders of magnitude. The lowest electrical resistivity value was 6.75 × 10−3 Ω cm, which was obtained in the 0.5 at% yttrium-doped ZnO thin film annealed in nitrogen with 5% hydrogen at 500 °C. In room-temperature photoluminescence (PL) spectra, two PL emission peaks are found in the pure ZnO thin film; one is the near-band-edge (NBE) emission at 3.22 eV and the other is a green emission at about 2.38 eV. Nevertheless, the green emission is not found in the PL of the yttrium-doped ZnO thin films. The low-temperature PL spectrum of the undoped ZnO thin film at 83 K is split into well-resolved free and bound excition emission peaks in the ultraviolet region, but the NBE emission of the 5 at% yttrium-doped ZnO thin film at 83 K has only one broad emission peak.

Transparent and conductive high preferential c-axis oriented ZnO thin films doped with yttrium have been prepared by sol–gel method using zinc acetate and yttrium chloride as cations source, 2-methoxyethanol as solvent and monoethanolamine (MEA) as sol stabilizer. Film deposition was performed by dip-coating technique at a withdrawal rate of 6.0 cm/min on silica glass substrates. The effect of dopant (Y) concentration, heating treatment and annealing in a reducing atmosphere on the structure, morphology, electrical and optical properties of ZnO thin films were investigated. When compared with the resistivity values of films without the annealing treatment, the values of films annealed in the reducing atmosphere were decreased by about three orders of magnitude. The lowest resistivity value was 6.75 × 10− 3 Ω cm, which was obtained in the 0.5 at.% yttrium-doped ZnO thin film annealed in nitrogen with 5% hydrogen at 500 °C. The average optical transmittance values of the annealed films were more than 80% in the visible range. The energy band gap calculated from the transmittance spectra is about 3.30–3.37 eV.

Faults are important pathways for fluid and hydrocarbon migration, and they play a crucial role in oil and gas migration and accumulation. But until now, the acquisition of evidence on fluid flow along a fault is still a puzzle. Based on studies of clay minerals, oil geochemistry and fluid inclusions in Shengbei fault zone, we find that: 1) distribution of illite is abnormal; 2) oil in the Sha-2 Member of the Shahejie Formation (Es2) and its overlying intervals was derived from the deep lower source rocks, i.e. the Sha-3 and Sha-4 Members of the Shahejie Formation (Es3 and Es4); and 3) fluid inclusions adjacent to F1 fault in the Es4 have mixed features of Es3 and Es4. These findings indicate that fluid and hydrocarbon migration (both vertical and lateral migration) once occurred along the F1 fault, that is, this fault once acted as a pathway for fluid and hydrocarbon migration.

Expression of recombination activating genes (RAG) involved in the V (D) J recombination is regulated by the RAG1 gene activator (RGA) in mammals. The sequence of a cDNA clone from an amphioxus cDNA library was found to be homologous to that of RGA from mouse stromal cells with 45% identity. The full-length cDNA sequence comprises 1119 bp and encodes a putative protein of 210 amino acid residues. Characterisation of the amino acid sequence revealed that two MtN3 domains and seven transmembrane spans are present in this protein, indicating a potential role as a plasma membrane protein. This gene is expressed in many tissues and at differential developmental stages. A high expression level of RGA is detected in gonad tissues, and gastrula embryo and adult stages. The presence of the RGA gene in amphioxus suggests that the signal pathway required for the expression of RAG could exist in this primitive protochordate. It also implies that in the related molecules, primitive adaptive immunity may have existed in cephalochordate although the complete machinery of VDJ rearrangement may not be formed.

In seeking evidence of the existence of adaptive immune system (AIS) in ancient chordate, cDNA clones of six libraries from a protochordate, the Chinese amphioxus, were sequenced. Although the key molecules such as TCR, MHC, Ig, and RAG in AIS have not been identified from our database, we demonstrated in this study the extensive molecular evidence for the presence of genes homologous to many genes that are involved in AIS directly or indirectly, including some of which may represent the putative precursors of vertebrate AIS-related genes. The comparative analyses of these genes in different model organisms revealed the different fates of these genes during evolution. Their gene expression pattern suggested that the primitive digestive system is the pivotal place of the origin and evolution of the AIS. Our studies support the general statement that AIS appears after the jawless/jawed vertebrate split. However our study further reveals the fact that AIS is in its twilight in amphioxus and the evolution of the molecules in amphioxus are waiting for recruitment by the emergence of AIS.

Macrophage migration inhibitory factor (MIF) is an important cytokine related to host defenses and autoimmune diseases. Here, we reported two full-length cDNA clones isolated from Chinese amphioxus (Branchiostoma belcheri tsingtaunese). Amino acid sequences analysis and structure prediction of these two molecules, called Bbt-MIF-I and Bbt-MIF-II, respectively, indicated that several conservative domains existed in the two amphioxus MIFs and their sequences were highly homologous to their counterparts of other species. Intriguingly, the Bbt-MIFs gene is present in multi-copy per haploid genome, which is very unusual compared with vertebrate's MIF gene given the known genome duplication theory. The genomic copy number, expression pattern of MIF gene and phylogenetic analysis of MIF proteins all suggested that a leap forward happened for MIF gene during the evolution from invertebrate to vertebrate. Considering the crucial role of MIF in innate immunity, MIF might serve as one of key molecular markers of evolution of immune system.

In situ electrical resistivity measurement of CdSe was performed under high pressure and moderate temperature using a diamond anvil cell equipped with a microcircuit. With the pressure increasing, a sharp drop in resistivity of over two orders of magnitude was observed at about 2.6 GPa, it was caused by the transition to the rock-salt CdSe. After that, the resistivity decreased linearly with pressure. However, in different pressure range, the decreasing degree was obviously different. This attributed to the different electron structures. By fitting to the curve of pressure dependence of resistivity in different pressure range, the relationship of the band gap to pressure was given and the metallization pressure was speculated to be in the range of 70–100 GPa. The temperature dependence of resistivity showed that in the experimental temperature and pressure range the resistivity had a positive temperature coefficient.

Recently, amphioxus has served as a model for studying the origin and evolution of vertebrate immunity. However, little is known about how microRNAs (miRNAs) are involved in the immune defense in amphioxus. In this article, we present a systematic study of amphioxus miRNAs in the acute-phase response to bacterial infection; miR-92d was found to regulate the complement pathway in this basal chordate. We identified all 155 possible miRNAs present in the amphioxus Branchiostoma belcheri genome by bioinformatics analyses, including 57 newly identified miRNAs (called bbe-miRNAs), and characterized the miRNA expression pattern. Four miRNAs (bbe-miR-7, bbe-miR-4868a, bbe-miR-2065, and bbe-miR-34b) were upregulated and bbe-miR-92d was downregulated under the challenge of both Vibrio anguillarum and Staphylococcus aureus bacteria. We further predicted miRNA targets and identified mRNA targets of immune-related miRNA using the hybrid PCR method. We propose that miR-92d regulates the complement pathway through targeting C3 for controlling the acute immune response to bacterial infections. This study provides evidence for the complex immune regulation of miRNAs in the acute-phase response in basal chordates.

The optimization of the airport gates assignment problem aims to improve the efficiency of gates allocation as well as the satisfaction degree of passengers. In this paper, an SWO algorithm combined with Tabu Search strategy was proposed to optimize the allocation of airport gates. Experimental results show that the improved SWO approach is more efficient than the conventional SWO approach.

As competition intensifies, more and more enterprises outsource their IT. It is very important to enterprises that how to make IT outsourcing success. Outsourcing Relationship is one of the key issues of IT outsourcing. This paper firstly introduces the importance of IT outsourcing relationship; secondly, it analyses evolution dynamic of IT outsourcing relationship: external power including government, competitors, technology, suppliers and internal power including enterprise's management ability, top management and outsourcing project; thirdly, it analyses evolution path of IT outsourcing relationship: support, alignment, reliance and alliance; lastly, it forms evolution mechanism model to explain evolution mechanism of enterprise IT outsourcing relationship.

In order to survive more and more enterprises have to put more attention to its core business and outsource its complex information technology. For many enterprises, what matters is no longer whether IT outsourcing should be practiced but how it should be well managed. Outsourcing Relationship is one of the key issues of IT outsourcing. This paper firstly reviews the literature about IT outsourcing relationships; secondly, it analyses dynamic mechanism of IT outsourcing relationship formation: external power including government, competitors, technology, suppliers' industrial level and internal power including enterprise's management ability, top management and outsourcing project; lastly, it forms one model and one analysis process to explain formation mechanism of enterprise IT outsourcing relationship.

It collected and processed the history data of their information system construction through an investigation of 222 enterprises in northeast old industrial base, explored the industry differences in growth process of information systems of enterprises. By analysis, we found that there were differences in the time of starting to implement informatization and starting to build a LAN, development mode and application field of information system of different industries. At last we concluded the reasons caused the differences, proposed several useful countermeasures and suggestions.

This paper studies how to enhance information technology (IT) absorption from the perspective of absorptive capacity. The research questions for this study are: What is the impact of absorptive capacity on a firm's IT absorption, and what would cause some firms to have a higher IT absorptive capacity than other firms? We examine the role of absorptive capacity in IT absorption, and identify five factors influencing IT absorptive capacity. The method of stochastic frontier estimation is used to estimate IT absorptive capacity and then explain the relationship between the five factors and IT absorptive capacity. Keywords-information technology(IT); IT absorption; IT absorptive capacity

Jawless vertebrates use variable lymphocyte receptors (VLR) comprised of leucine-rich-repeat (LRR) segments as counterparts of the immunoglobulin-based receptors that jawed vertebrates use for antigen recognition. Highly diverse VLR genes are somatically assembled by the insertion of variable LRR sequences into incomplete germline VLRA and VLRB genes. Here we show that in sea lampreys (Petromyzon marinus) VLRA and VLRB anticipatory receptors are expressed by separate lymphocyte populations by monoallelic VLRA or VLRB assembly, together with expression of cytosine deaminase 1 (CDA1) or 2 (CDA2), respectively. Distinctive gene expression profiles for VLRA(+) and VLRB(+) lymphocytes resemble those of mammalian T and B cells. Although both the VLRA and the VLRB cells proliferate in response to antigenic stimulation, only the VLRB lymphocytes bind native antigens and differentiate into VLR antibody-secreting cells. Conversely, VLRA lymphocytes respond preferentially to a classical T-cell mitogen and upregulate the expression of the pro-inflammatory cytokine genes interleukin-17 (IL-17) and macrophage migration inhibitory factor (MIF). The finding of T-like and B-like lymphocytes in lampreys offers new insight into the evolution of adaptive immunity.

This paper takes three typical information systems (financial system, office automatic system, and enterprise resource planning system) as examples to study information technology (IT) adoption of Chinese enterprises by means of survival analysis. The dimension of time and dynamic characteristic of IT adoption are highly emphasized in this paper. The method of Kaplan-Meier analysis is used to compare the difference of survival time of IT adoption for heterogeneous enterprises, and the resulting survival functions reflect the adoption proportion at a particular time. Then Cox regression model is used to examine the impact of enterprise characteristics on IT adoption. The results demonstrate that their impact varies with the target technology. Further, this study indicates the direction and significance of the impact of enterprise characteristics on the three technologies respectively.

The mechanism of information system (IS) growth is an important part of IS growth theory and has attracted much attention of scholars and entrepreneurs. As validated by many studies, the process of IS growth is influenced by various factors within the enterprise and from external environment. The external factors are mainly governmental propulsion, competitive pressure, linkage demand of cooperative enterprises and IT suppliers’ propulsion. The internal factors are top management support, middle management support, IT department propulsion and other organizational personnel’s cooperation and participation. The synergic effect of internal and external factors promotes the development of IS construction and the growth of enterprise information systems. This paper pays more attention to the microcosmic mechanism of IS growth and proposes that IT absorption is a direct impetus to IS growth. It analyzes synergic effect of the subjects and elements of IT absorption. Furthermore, a mathematic model is used to describe the spiral-propulsion mode of IS growth. Viewed from a holistic perspective, IS growth presents itself as a dynamic and spiral process.

Large-scale uniform dumbbell-like ZnO microcrystals were successfully synthesized via a facile solution method under mild conditions. The as-prepared dumbbells, with lengths of 3.5-5.4 microm and diameters of 1.3-1.8 microm, possess a single-crystal hexagonal structure and grow along the [0001] direction. The influence of the reactant concentration on the size and shapes of the ZnO samples had been studied, and the results revealed that the reactant concentration plays a crucial role in determining final morphologies of the samples. Moreover, the evolution process of the dumbbell-like ZnO microcrystals was viewed by field-emission scanning electron microscopy (FE-SEM) characterization, and a possible formation mechanism was proposed. In addition, optical properties of the ZnO samples prepared at different reaction times were also investigated by photoluminescence (PL) spectroscopy. The room-temperature PL spectrum of the dumbbell-like ZnO microcrystals shows a strong UV emission peak. The UV emission is further identified to originate from the radiative free-exciton recombination by the temperature-dependent PL.