Diaqua­bis­(2,2′-bi-1H-imidazole)­man­ganese(II) benzene-1,4-di­carboxyl­ate

The asymmetric unit of the title compound, [Mn(C6H6N4)2(H2O)2](C8H4O4), contains one-half each of the centrosymmetric cation and anion. The MnII atom is coordinated by four N atoms [Mn—N = 2.2168 (14) and 2.2407 (14) Å] from two 2,2′-biimidazole ligands and two water mol­ecules [Mn—O = 2.2521 (14) Å] in a distorted octa­hedral geometry. Inter­molecular N—H⋯O and O—H⋯O hydrogen bonds consol­idate the crystal packing, which also exhibits π–π inter­actions between five-membered rings, with a centroid–centroid distance of 3.409 (2) Å

Improvement of Electron Probe Microanalysis of Boron Concentration in Silicate Glasses

The determination of low boron concentrations in silicate glasses by electron probe microanalysis (EPMA) remains a significant challenge. The internal interferences from the diffraction crystal, i.e. the Mo-B4C large d-spacing layered synthetic microstructure crystal, can be thoroughly diminished by using an optimized differential mode of pulse height analysis (PHA). Although potential high-order spectral interferences from Ca, Fe, and Mn on the BKα peak can be significantly reduced by using an optimized differential mode of PHA, a quantitative calibration of the interferences is required to obtain accurate boron concentrations in silicate glasses that contain these elements. Furthermore, the first-order spectral interference from ClL-lines is so strong that they hinder reliable EPMA of boron concentrations in Cl-bearing silicate glasses. Our tests also indicate that, due to the strongly curved background shape on the high-energy side of BKα, an exponential regression is better than linear regression for estimating the on-peak background intensity based on measured off-peak background intensities. We propose that an optimal analytical setting for low boron concentrations in silicate glasses (≥0.2 wt% B2O3) would best involve a proper boron-rich glass standard, a low accelerating voltage, a high beam current, a large beam size, and a differential mode of PHA

Inter-layer free cobalt-doped silica membranes for pervaporation of ammonia solutions

This study demonstrated the application of a new type of interlayer-free cobalt-doped silica membrane in treating ammonia solutions by pervaporation applied towards wastewater treatment. For enhanced hydrothermal stability, cobalt-doped silica (CoSi) membranes with increasing cobalt concentrations from 1 to 35 mol% were prepared and evaluated, namely CoSi-1, 5, 20 and 35. These membranes exhibited high water fluxes of 66 L m h for CoSi-1 and 15.5 L m h for CoSi-35 at 45 °C. The fluxes of the membranes decreased with increasing cobalt concentration; while the rejection to total nitrogen (TN, ammonia nitrogen) increased and hence allowed selective passage of water molecules. Enhanced thermostability was observed for the membranes, particularly CoSi-35 that exhibited TN rejection up to 99% at high temperature of 65 °C and highly alkaline environment (pH > 10). Also, the CoSi-35 membrane showed stable performance in treating ammonia present in industry wastewater by achieving stable TN and mineral rejections of 97% and 99%, respectively. Fouling was observed and confirmed by SEM morphological analysis and EDX elemental inspection. The results indicated the deposition of low solubility salts such as CaSO

A Magnetically and Thermally Controlled Liquid Metal Variable Stiffness Material

Smart materials that can actively tune their stiffness are of great interest to many fields, including the construction industry, medical devices, industrial machines, and soft robotics. However, developing a material that can offer a large range of stiffness change and rapid tuning remains a challenge. Herein, a liquid metal variable stiffness material (LMVSM) that can actively and rapidly tune its stiffness by applying an external magnetic field or by changing the temperature is developed. The LMVSM is composed of three layers: a gallium–iron magnetorheological fluid (Ga–Fe MRF) layer for providing variable stiffness, a nickel–chromium wire layer for Joule heating, and a soft heat dissipation layer for accelerating heating and rapid cooling. The stiffness can be rapidly increased by 4 times upon the application of a magnetic field or 10 times by solidifying the Ga–Fe MRF. Finally, the LMVSM is attached to a pneumatically controlled soft robotic gripper to actively tune its load capacity, demonstrating its potential to be further developed into smart components that can be widely adopted by smart devices

A new superimposed model of the Tongnanba anticline in northeastern Sichuan and its exploration implications

Understanding the structural style, kinematic process, and timing of superimposed structures worldwide is often difficult due to complex structure deformation process. Fortunately, the newly acquired high-quality seismic reflection data and geological observations covering the Tongnanba anticline provide an excellent chance to characterize such structures. Here, we used geological and seismic data from the Tongnanba region to evaluate the structural style and deformation sequence of Tongnanba anticline. In this regard, we propose a new model of the northeastern Sichuan Basin, which are different from the model that deep structures formed earlier than shallow structures demonstrated by previous studies, and we also discussed the implications of this new model for the deep oil and gas exploration. Compressed by Micangshan and Dabashan thrust belts and controlled by three detachment layers, the Tongnanba anticline shows a complex multi-stage, multi-directional, and multi-level superimposed structure. There were three deformation layers vertically, leading to the multi-level detachment thrust structure style. Specifically, the upper and middle deformation layers were mainly controlled by South Dabashan thrust belt in the early stage, forming long-distance detachment thrust structure extended in the NW-SE direction. A series of pop-up structures propagated toward the upper and middle detachment layers. On the other hand, the lower deformation layer was primarily controlled by the Micangshan thrust belt in the late stage, forming complex basement faults extended in the NE-SW direction, which was consistent with Trishear fault-propagation fold. Along the basement detachment developed multiple branch slopes spread from northeast to southwest. The middle and upper deformation layers was transformed by the basement faults, thus forming the complex superimposed structure of north-south zonation and east-west segmentation at present. It was such complex superimposed structure that control the process of hydrocarbon accumulation and adjustment in each deformation layer, and the deep-ultra-deep ancient oil and gas reservoirs may be worth of exploring

Characterization of the Resistance and Force of a Carbon Nanotube/Metal Side Contact by Nanomanipulation

A high contact resistance restricts the application of carbon nanotubes (CNTs) in fabrication of field-effect transistors (FETs). Thus, it is important to decrease the contact resistance and investigate the critical influence factors such as the contact length and contact force. This study uses nanomanipulation to characterize both the resistance and the force at a CNT/Au side-contact interface inside a scanning electron microscopy (SEM). Two-terminal CNT manipulation methods, and models for calculating the resistance and force at contact area, are proposed to guide the measurement experiments of a total resistance and a cantilever’s elastic deformation. The experimental results suggest that the contact resistance of CNT/Au interface is large (189.5 kΩ) when the van der Waals force (282.1 nN) dominates the contact force at the interface. Electron-beam-induced deposition (EBID) is then carried out to decrease the contact resistance. After depositing seven EBID points, the resistance is decreased to 7.5 kΩ, and the force increases to 1339.8 nN at least. The resistance and force at the contact area where CNT was fixed exhibit a negative exponential correlation before and after EBID. The good agreement of this correlation with previous reports validates the proposed robotic system and methods for characterizing the contact resistance and force

Hard superconducting gap in PbTe nanowires

Semiconductor nanowires coupled to a superconductor provide a powerful testbed for quantum device physics such as Majorana zero modes and gate-tunable hybrid qubits. The performance of these quantum devices heavily relies on the quality of the induced superconducting gap. A hard gap, evident as vanishing subgap conductance in tunneling spectroscopy, is both necessary and desired. Previously, a hard gap has been achieved and extensively studied in III-V semiconductor nanowires (InAs and InSb). In this study, we present the observation of a hard superconducting gap in PbTe nanowires coupled to a superconductor Pb. The gap size ($\Delta$) is $\sim$ 1 meV (maximally 1.3 meV in one device). Additionally, subgap Andreev bound states can also be created and controlled through gate tuning. Tuning a device into the open regime can reveal Andreev enhancement of the subgap conductance, suggesting a remarkable transparent superconductor-semiconductor interface, with a transparency of $\sim$ 0.96. These results pave the way for diverse superconducting quantum devices based on PbTe nanowires

Comparative efficacy and acceptability of antidepressants, psychological interventions, and their combination for depressive disorder in children and adolescents:protocol for a network meta-analysis

Introduction Depressive disorder is common in children and adolescents, with important consequences and serious impairments in terms of personal and social functioning. While both pharmacological and psychological interventions have been shown to be effective, there is still uncertainty about the balance between these and what treatment strategy should be preferred in clinical practice. Therefore, we aim to compare and rank in a network meta-analysis (NMA) the commonly used psychological, pharmacological and combined interventions for depressive disorder in children and adolescents. Methods and analysis We will update the literature search of two previous NMAs for the identification of trials of antidepressant and psychotherapy alone for depressive disorder in children and adolescents. For identification of trials of combination interventions, seven databases (PubMed, EMBASE, CENTRAL (Cochrane Central Register of Controlled Trials), Web of Science, PsycINFO, CINAHL, LiLACS) will be searched from date of inception. We will also search ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform and check relevant reports on the US Food and Drug Administration website for unpublished data. Building on our previous findings in the field, we will include any commonly prescribed oral antidepressants and any manualised or structured psychotherapies, as well as their combinations. Randomised controlled trials assessing any active intervention against active comparator or pill placebo/psychological controls in acute treatment for depressive disorder in children and adolescents will be included. The primary outcomes will be efficacy (mean change in depressive symptoms), and acceptability of treatment (dropout rate due to any cause). The secondary outcomes will be remission rate, tolerability of treatment (dropouts for adverse events), as well as suicide-related outcomes (suicidal behaviour or ideation). We will perform Bayesian NMAs for all relative outcome measures. Subgroup analyses and sensitivity analyses will be conducted to assess the robustness of the findings. Dissemination This NMA will provide the most up to date and clinically useful information about the comparative efficacy and acceptability of antidepressants, psychological intervention and their combination in the acute treatment of children and adolescents with depressive disorder. This is the newest NMA and therefore these results are very important in terms of evidence-based medicine. The results will be disseminated through peer-reviewed publication. Protocol registration PROSPERO CRD42015020841