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Superconducting microwave resonators are reliable circuits widely used for detection and as test devices for material research. A reliable determination of their external and internal quality factors is crucial for many modern applications, which either require fast measurements or operate in the single photon regime with small signal to noise ratios. Here, we use the circle fit technique with diameter correction and provide a step by step guide for implementing an algorithm for robust fitting and calibration of complex resonator scattering data in the presence of noise. The speedup and robustness of the analysis are achieved by employing an algebraic rather than an iterative fit technique for the resonance circle. [ABSTRACT FROM AUTHOR]

The article reports that lead magnesium niobate-lead titanate (PMN-PT) has been widely investigated for its excellent dielectric and piezoelectric properties, which makes it an ideal material for applications in multiplayer ceramic capacitors, piezoelectric transducers and solid-state actuators. The pure perovskite PMN-PT powders can be obtained at the temperature of 750 degrees by the rutile precursor method. The phase formation and stability were measured by a simultaneous thermogravimetric analysis and differential thermal analysis.

Summary: Sustainable agricultural management practices improve soil processes, prevent soil erosion and consequently enhance crop productivity. The integrated agricultural practice (IP) developed in northeast China, by altering row spacing of planting, adopting no‐tillage and returning all crop residues, showed great benefit in sustaining crop yield. However, its effect on the soil microbiome remains largely elusive. This study evaluated the effect of 12‐year integrated agricultural practice on the structure and activity of the soil microbial community at different soil depths in China's Mollisols zone. The experiment consisted of integrated agricultural practice and conventional practice (CP) treatments in a split‐plot arrangement. The soil microbial community was characterized by MiSeq sequencing. The results showed that agricultural practices affected 12 phyla, 24 classes, 32 orders and 75 families in the bacterial community and one phyla, four classes, 12 orders and 18 families in the fungal community. Integrated agricultural practice resulted in greater bacterial richness and diversity, and increased the relative abundances of Actinobacteria, Gemmatimonadetes, Verrucomicrobia and Ascomycota, but reduced Bacteroidetes, Firmicutes and Basidiomycota in the dominant bacterial and fungal phyla. These findings suggested that integrated agricultural practice modified the soil physiochemical properties and consequently altered microbial community structure and diversity, which in turn affected soil microbial biomass and enzyme activities. These changes under integrated agricultural practice could have contributed to the enhanced crop yield, suggesting that IP is a sustainable agricultural practice. Highlights: How does soil microbial community change in the IP and CP soils? IP affected the soil microbial community and activity. Bacterial and fungal community structure correlated significantly with soil physiochemical properties. IP is a promising sustainable agricultural practice. [ABSTRACT FROM AUTHOR]

In this paper, a new high-temperature superconducting (HTS)-based microwave radiometer with an improved sensitivity is presented. The cryogenic receiver front end consists of an HTS filter and a cryogenic low noise amplifier (LNA). The cryogenic receiver front end shows an ultra-low noise figure and can suppress radio frequency interference (RFI) effectively. The proposed HTS filter works at a center frequency of 1.4135 GHz with a bandwidth of 25 MHz. The measured mid-band insertion loss, side band steepness, and out-of-band attenuation of the HTS filter are 0.14 dB, 35 dB/MHz, and 80 dB, respectively. The noise figure of the cryogenic LNA is about 0.27 dB at a temperature of 77 K. Compared with other total power radiometers, the proposed radiometer has a lower receiver noise temperature, which can improve the sensitivity with a short integration time of the satellite-based salinity meter. In addition, since the bandwidth of the salinity meter is fixed and the integration time of satellite-based equipment is limited, such a low receiver noise temperature can increase the flexibility of future satellite payload configuration program. [ABSTRACT FROM AUTHOR]

Nonlinear inductance of intrinsic Josephson junction arrays in Tl-2212 thin films has been investigated. Misaligned Tl-2212 thin films were fabricated on 20° vicinal LaA1O3 substrates and then patterned into long bridges by standard photolithography and wet chemical etching. Each bridge forms a large array of intrinsic Josephson junctions. We have measured the Josephson inductance of the bridges in the zero-DC-voltage state at 77 K and show that its dependence on the critical current is in a good agreement with theory. Also, we have numerically studied the nonlinearity of the Josephson inductance and present dependence of the distortion factor on the bias and AC signal currents. Based on the obtained results, we have designed a 10-pole narrow-band lumped-element filter with the tunable center frequency in the range from 1900 MHz to 1960 MHz. Simulations show that the filter has good selectivity. [ABSTRACT FROM AUTHOR]