Effective Room-Temperature Ammonia-Sensitive Composite Sensor Based on Graphene Nanoplates and PANI

The graphene nanoplate (GN)-polyaniline (PANI) composite was developed via in-situ polymerization method and simultaneously assembled on interdigital electrodes (IDEs) at low temperature for ammonia (NH3) detection. The assembled composite sensor showed excellent sensing performance toward different concentrations of NH3, 1.5 of response value and 123 s/204 s for the response/recovery time to 15 ppm NH3. Meanwhile, an interesting supersaturation phenomenon was observed at high concentration of NH3. A reasonable speculation was proposed for this special sensing behavior and the mechanism for enhanced sensing properties was also analyzed

Intelligent Mining of Urban Ventilation Corridors Based on High-Precision Oblique Photographic Images

With the advancement of urbanization and the impact of industrial pollution, the issue of urban ventilation has attracted increasing attention. Research on urban ventilation corridors is a hotspot in the field of urban planning. Traditional studies on ventilation corridors mostly focus on qualitative or simulated research on urban climate issues such as the intensified urban heat island effect, serious environmental pollution, and insufficient climate adaptability. Based on the high-precision urban remote sensing image data obtained by aeromagnetic oblique photography, this paper calculates the frontal area density of the city with reference to the urban wind statistics. Based on the existing urban patterns, template matching technology was used to automatically excavate urban ventilation corridors, which provides scientific and reasonable algorithmic support for the rapid construction of potential urban ventilation corridor paths. It also provides technical methods and decision basis for low-carbon urban planning, ecological planning and microclimate optimization design. This method was proved to be effective through experiments in Deqing city, Zhejiang Province, China

Initial Experience with Hybrid Partial Nephrectomy with Ultrasound-guided Balloon Catheter Occlusion of the Renal Artery for Recurrent Renal Tumors

Repeat partial nephrectomy (PN) is an effective treatment in improving the prognosis for patients with recurrent renal cancer after initial PN. However, salvage PN (sPN) is inevitably associated with a higher rate of complications, largely because of intraperitoneal adhesions and fibrosis. Here we describe three initial cases for which recurrent renal tumors were treated with a novel minimally invasive approach, namely Ultrasound-guided Renal Artery Balloon catheter Occluded Hybrid Partial Nephrectomy (UBo-HPN).With laparoscopic ultrasound (LUS) guiding a Fogarty catheter to occlude the arterial blood supply, dissection of the renal hilum and most of the abdominal cavity can be avoided. UBo-HPN was successfully performed in three patients. One case of postoperative fever (Clavien-Dindo grade II) occurred, with no other complications. The mean operative time was 106 min, with a mean warm ischemia time of 21 min. UBo-HPN may be considered a safe and effective alternative for sPN, with a minimally invasive surgical footprint and better surgical outcomes

Liquid Sn corrosion behaviors to high-flux hydrogen plasmas irradiated Mo capillary-pore systems

This paper studied the effects of hydrogen plasma irradiation on the corrosion resistance of Mo capillary porous systems (CPSs) in high temperature liquid Sn. Initial Mo CPSs showed a significant morphology change and mass loss rate (1.107 × 10–3 mg/(mm2·h)) after corrosion in liquid Sn at 1,023 K for 100 h. A brief period of irradiation enhanced the corrosion resistance of Mo wires, resulting in a dramatic decrease to 1.23 × 10–4 mg/(mm2·h) in mass loss rate under the same corrosion conditions. To determine whether temperature was the main factor leading to above phenomenon, Mo CPSs were pre-annealed at the same temperature (843 K) as irradiation. The mass loss rate of annealed Mo CPSs (3.09 × 10–4 mg/(mm2·h)), which was lower than that of the initial sample, was still higher than that of the plasma-treated samples. Difference between plasma irradiation and heat treatment was the incident of various particles in hydrogen plasma. Therefore, the suppressed corrosion phenomenon caused by plasma could not only be attributed to the function of high temperature but its synergistic effect with hydrogen isotope retention

The investigation of chemical vapor deposited copper-based niobium films

The deposition of niobium film on copper with excellent superconducting property at low-temperature conditions, used as superconducting radio frequency (SRF) cavity, is a serious and urgent technical problem to be solved at present. In this work, copper-based niobium (Nb) films with a thickness of 1.5–1.8 um, regulating the deposition temperature parameters and gas flow velocity in a tube furnace, were prepared by low-temperature chemical vapor depositing (CVD) method from the reaction between H _2 and Niobium chloride (NbCl _5 ) under pure Ar atmosphere. Fabricated Nb films were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy, respectively. The results showed that the excellent crystalline quality and superconductive performance of Nb films were generated successfully by CVD at low temperatures of 650 °C–700 °C. The preparation process was optimized during deposition and the formation mechanism of Nb films was also discussed in detail. The magnetic moment versus temperature of the Nb sample prepared at 700 °C was also measured and the well-prepared Nb film deposited in the boundary layer region obtains the desired superconducting transition temperature of 9.1 K ± 0.1 K, almost equivalent to that of high pure Nb bulk material. The optimized CVD reaction method of Nb film with favorable morphology and expected superconductive property at low temperature provided a new strategy and technical process in designing the desired copper-based Nb film SRF cavity