Molybdenum oxide based sensors

In this review article were considered the works of electrochemical sensors modified with molybdenum oxide. The work of sensors based on molybdenum oxide was systematized, a comparison table was developed, the sensors were classified according to the purpose of use. Methods of molybdenum oxide synthesis used to modify the working electrode in electrochemical sensors were considered. The various methods have been used to synthesize molybdenum oxide, such as a thermal, hydrothermal, electrochemical, electric spark, pulsed laser method, acid condensation, electrophoretic precipitation, pulse potential precipitation. The main parameters of the molybdenum oxide modified sensors, such as the detection limit, linear range, response time, sensitivity, and other parameters were compared. As a result of studies, it was found that molybdenum oxide is selected as a modifying material in electrochemical sensors due to the unique physicochemical properties of molybdenum oxide, in particular because of mechanical strength, electrical conductivity, electro catalytic activity, crystallinity. The features of electrochemical biosensors coated with molybdenum oxide were described for the detection of important compounds in specific samples. Sensors based on molybdenum oxide have been used for detection of glucose, dopamine, ethanol, ascorbic acid, troponin-1, norepinephrine, procalcitonin, L-lactate, bromate, chlorate, E110, tartrazine, hydrochlorothiazide, human epidermal growth factor-2, lithium,sodium,potassium. This paper provides general summarized information about current aspects of research works related to electrochemical sensors based on molybdenum oxide.

Spatial Heterogeneity of Soil Respiration Response to Precipitation Pulse in a Temperate Mixed Forest in Central China

Water availability is one of the fundamental drivers for biological activities and terrestrial carbon cycling. Although the response of soil respiration to precipitation has been well documented in arid and semiarid ecosystems, our understanding of its pattern in forests is rather limited. This study was conducted to examine the difference of precipitation effect on soil respiration under different canopy conditions in a temperate coniferous (Pinus armandii Franch) and broadleaved (Quercus aliena var. acuteserrata) mixed forest in Central China. The results showed that precipitation significantly reduced soil temperature, but increased soil volumetric water content and soil respiration (6.0%-35.3%). Precipitation caused a greater increment in soil respiration beneath the canopy of broadleaved trees (24.2%) than that beneath coniferous ones (13.5%). Precipitation-induced increase in soil respiration was consistently lower beneath the canopy of small size classes (7.1%-32.6%) than large size classes (9.5%-33.3%). Mean soil respiration of forest gaps increased 22.4% following precipitations. Our study highlights the positive response of soil respiration to precipitation pulses in water-unlimited ecosystems. The findings suggest that the spatial heterogeneity of soil respiration to precipitation pulse under different canopy conditions should be emphasized while assessing terrestrial carbon cycling and its feedback to climate change.