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The shrub and patch size of moss crusts can significantly affect plant and soil nutrients. The effects and relationships of shrubs and moss crusts on soil multifunctionality are unclear. This study aimed to understand the spatial heterogeneity of soil multifunctionality in moss crust patches and shrubs. Soil organic carbon, nutrient, and enzyme activities under moss crust patches were measured. Interestingly, the soil polyphenol oxidase (PPO) and peroxidase (POD) activities, carbon‐related soil multifunctionality index (C‐SMF), nitrogen‐related soil multifunctionality index (N‐SMF), phosphorus‐related soil multifunctionality index (P‐SMF), and soil multifunctionality index (SMF) increased with increasing patch size in moss crusts. The patch size of moss crusts had no significant effect on the C‐SMF, N‐SMF, P‐SMF, and SMF under the shrub. The soil C‐SMF, N‐SMF, P‐SMF, and SMF under shrubs were significantly higher than that in exposed areas (EAs). The soil PPO, POD, N‐SMF, P‐SMF, and SMF under dead shrubs were significantly higher than those under living shrubs and in EAs. Evaluation and composition analysis of C‐SMF, N‐SMF, and P‐SMF indicated that moss crust promotes the increase of P‐SMF, and that shrub promotes the increase of C‐SMF and N‐SMF. Moss crust patches mainly affected phosphorus functionality, increasing phosphorus cycling. Shrub promotes soil carbon and nitrogen functionality. This study elucidates the effect of moss crust patch size on soil multifunctionality influenced by shrub growth in desert ecosystems and provides further new insights into the soil processes and functions. Results are beneficial for the comprehensive utilization of fertile islands and its enhancement of beneficial ecological functions, such as maintaining soil nutrition, quality, health, and vegetation restoration, and lay a foundation for future research on nutrient absorption and utilization between mosses and shrubs. Core Ideas: The patch size effect of moss crusts is a positive in soil multifunctionality and is influenced by microhabitats.Moss crust patches mainly affected phosphorus functionality, increasing phosphorus cycling.Shrub patches mainly affected soil carbon and nitrogen functionality. [ABSTRACT FROM AUTHOR]

Mercury can indicate the presence of deposits or mineralization, which is an important tracer element of geological processes, thus making the determination of mercury very important. Due to the low abundance of mercury in ore deposits, it is difficult to directly determine and thus pre-separation enrichment is needed. Presently, most of the separation and preconcentration methods are off-line with a low degree of automation. Graphene oxide/chitosan microspheres modified by dithizone were prepared and applied as adsorption materials for solid phase extraction column. The effect of experimental parameters including acidity, adsorbent type, and adsorption volume on the absorption efficiency was evaluated. Sampling/elution time and the sampling/elution rate during solid phase extraction were optimized. Based on these conditions, an analytical method for the determination of trace mercury in geological samples by on-line enrichment-atomic fluorescence spectrometry with solid phase extraction was established. The results show that when the pH value is 3.0, the adsorption rate of mercury is more than 90% at 5 mL/min sampling rate. The elution rate was >95% when 20 g/L of thiourea and 1.0 mol/L HNO3 were used as elution solution and elution for 1 min at the rate of 1 mL/min. The working curve showed a good linear relationship when the concentration was between 0.050 μg/L and 5.0 μg/L. The enrichment factor was 22 and the detection limit was 0.0019 μg/L. The relative error of the measured value of Hg and the reference value was less than ±13% when this method was used to determine soil and sediment national standard materials. Compared with the off-line analysis, this method has advantages such as high sensitivity and simple operation.

Identification of porosity in shale is of great significance for exploring mechanism of shale gas. Porosity properties of the shale samples from the Ordos Basin were characterized by multiple techniques including Scanning Electron Microscope(SEM), Mercury Intrusion Porosimetry(MIP), and nitrogen gas adsorption-desorption. Results showed that the shales contained abundant pores that include dissolution pore, microfracture pore, and intergranular pore. The pore sizes range from several to several hundred nanometers. The total surface area ranges from 5.06 to 19.32 m2/g and pore volume has a range of 0.01-0.03 cm3/g. Results indicate that the OrdosBasin Shale develops pores of various types and sizes. The main type of pore is the nano-pore, which is beneficial for the storage of shale gas. Micro-cracks are beneficial for the transportation of shale gas. These results suggest that the basic environment of the Ordos Basin is suitable for the storage of shale gas and that the Ordos Basin may be rich in shale gas.

A reconfigurable differential-to-single-ended autonomous current adaptation buffer amplifier (ACABA) is proposed. The ACABA, based on floating-gate technologies, is a capacitive circuit, of which output DC level and bandwidth can be adjusted by programming charges on floating nodes. The gain is variable by switching different amounts of capacitors without altering the output DC level. Without extra sensing and control circuitries, the current consumption of the proposed ACABA increases spontaneously when the input signal is fast or large, achieving a high slew rate. The supply current dwindles back to the low quiescent level autonomously when the output voltage reaches equilibrium. Therefore, the proposed ACABA is power-efficient and suitable for processing physiological signals. A prototype ACABA has been designed and fabricated in a $\text{0.35}\thinspace \mu \text{m}$ CMOS process occupying an area of $\text{0.151}\thinspace \text{mm}^{2}$. When loaded by a $\text{10}\thinspace \text{pF}$ capacitor, it consumes $\text{3}\thinspace \mu \text{W}$ to achieve a unity-gain bandwidth of $\text{100}\thinspace \text{kHz}$ with a measured IIP2 value of $\text{52.66}\thinspace \text{dBV}$ and a slew rate of $\text{7.86}\thinspace \text{V}/\thinspace \mu \text{s}$. [ABSTRACT FROM AUTHOR]

Samples of sea-surface microlayer (SML) and sub-surface water (SSW) were collected from two areas-Kaohsiung City (Taiwan) and the southwest coast of Peninsular Malaysia to study the influence of SML on enrichment and distribution and to compare SML with the SSW. Anionic surfactants (MBAS) predominated in this study and were significantly higher in Kaohsiung than in Malaysia. Industrial areas in Kaohsiung were enriched with high loads of anthropogenic sources, accounted for higher surfactant amounts, and pose higher environmental disadvantages than in Malaysia, where pollutants were associated with agricultural activities. The dissolved organic carbon (DOC), MBAS, and cationic surfactant (DBAS) concentrations in the SML correlated to the SSW, reflecting exchanges between the SML and SSW in Kaohsiung. The relationships between surfactants and the physiochemical parameters indicated that DOC and saltwater dilution might affect the distributions of MBAS and DBAS in Kaohsiung. In Malaysia, DOC might be the important factor controlling DBAS. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in the sea-surface microlayer (SML) and sub-surface water (SSW) were analyzed in and around Kaohsiung Harbor. The results confirm SML enrichments for PAHs, but PCBs less significantly, since PAHs are still produced while PCBs had banned years ago. However, PCBs still leak to the environment from contaminated sites. The results showed the sources and transport of PAHs and PCBs were different, but both are enriched in the SML. Total particulate PAHs at most sites are below the toxicity thresholds, with a few individual PAHs between the effects range-low and effect range-median even higher than the effect range-median. Total particulate PCBs might cause occasionally adverse effects in sensitive species and pose a risk to the organisms. The particulate phase in the SML poses a higher risk to the marine ecosystem than in the SSW although not all organisms will make direct use of the microlayer. Principal component analysis (PCA) of PAHs indicated the important contribution of traffic engine emission in the particulate samples of the SML and SSW and revealed that probably the petroleum pollutants are a predominant source for the dissolved phase. Cluster analysis revealed that PAH-PCB patterns in the river and anchorage channels were different to those in the wetlands and open harbor. However, PCA of PCBs showed differences in the congener profiles for the two phases, with highly chlorinated PCBs more abundant in particles, while less chlorinated PCBs were more abundant in dissolved. Image 1 • PAHs and PCBs were enriched in the SML, both for particles and dissolved compounds. • Particles in the SML poses a higher risk to the marine ecosystem than in the SSW. • Cluster analysis revealed that PAH-PCB patterns were different between sites. • Distinctive microlayer enrichment behaviors between PAH and PCB were found. [ABSTRACT FROM AUTHOR]