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Fast pyrolysis of cellulose, xylan, and lignin was experimentally conducted between 350 and 650 °C in a tube furnace, and the effect of temperature on pyrolysis products (char, noncondensable gas, and bio-oil) was investigated. The yields of char, noncondensable gas, and bio-oil were quantified using gas chromatography and gas chromatography with mass spectrometry. The noncondensable gas mainly consists of CO, CO 2 , CH 4 , and H 2 . The bio-oil includes acids, ketones, aldehydes, esters, benzenes, alcohols, alkenes, phenols, alkanels, carbohydrates, etc. The results show that cellulose is the principal source of carbohydrates and phenols are the basis of the bio-oil from lignin, while the bio-oil from xylan mainly consists of acids, ketones, aldehydes, and phenols. The char yields for the three components decrease with an increase in temperature, and the gas yields and bio-oil yields increase with an increase in temperature, reach a maximum at a certain temperature, and then decrease after that temperature. The maximum biooil yields for cellulose, xylan, and lignin are 65, 53, and 40%, respectively; and their corresponding temperatures are 400, 450, and 500 °C, respectively. To investigate a relationship between biomass and three major components (hemicellulose, cellulose, and lignin), the pyrolysis of three typical biomass samples (rice straw, corn stalk, and peanut vine) was also studied, and the additivity law is adopted to predict the product components of biomass pyrolysis based on the content of hemicelluloses, cellulose, and lignin. The results show that the additivity law can predict reasonably the trend of product yields of biomass samples from their composition of hemicelluloses, cellulose, and lignin.

Background:Wernicke’s concept of ‘sejunction’ or aberrant associations among specialized brain regions is one of the earliest hypotheses attempting to explain the myriad of symptoms in psychotic disorders. Unbiased data mining of all possible brain-wide connections in large data sets is an essential first step in localizing these aberrant circuits.Methods:We analyzed functional connectivity using the largest resting-state neuroimaging data set reported to date in the schizophrenia literature (415 patients vs. 405 controls from UK, USA, Taiwan, and China). An exhaustive brain-wide association study at both regional and voxel-based levels enabled a continuous data-driven discovery of the key aberrant circuits in schizophrenia.Results:Results identify the thalamus as the key hub for altered functional networks in patients. Increased thalamus–primary somatosensory cortex connectivity was the most significant aberration in schizophrenia (P=10−18). Overall, a number of thalamic links with motor and sensory cortical regions showed increased connectivity in schizophrenia, whereas thalamo–frontal connectivity was weakened. Network changes were correlated with symptom severity and illness duration, and support vector machine analysis revealed discrimination accuracies of 73.53–80.92%.Conclusions:Widespread alterations in resting-state thalamocortical functional connectivity is likely to be a core feature of schizophrenia that contributes to the extensive sensory, motor, cognitive, and emotional impairments in this disorder. Changes in this schizophrenia-associated network could be a reliable mechanistic index to discriminate patients from healthy controls.

With the advancement in high-resolution magnetic resonance imaging (MRI) technology and automated analysis, studies on functional MRI (fMRI) made it possible to identify the functional activity of brain in vivo in individuals with Internet gaming disorder (IGD), and to explore the underpinning neuroscience basis of IGD. Yet, no available literature has systemically reviewed the fMRI studies of IGD using meta-analyses. This study reviewed 61 candidate articles and finally selected 10 qualified voxel-wise whole-brain analysis studies for performing a comprehensive series of meta-analyses employing effect size signed differential mapping approach. Compared with healthy controls, subjects with IGD showed a significant activation in the bilateral medial frontal gyrus (MFG) and the left cingulate gyrus, as well as the left medial temporal gyrus and fusiform gyrus. Furthermore, the on-line time of IGD subjects was positively correlated with activations in the left MFG and the right cingulated gyrus. These findings implicate the important role of dysfunctional prefrontal lobe in the neuropathological mechanism of IGD. Considering the overlapped role of prefrontal lobe in the reward and self-regulatory system, our results provided supportive evidence for the reclassification of IGD as a behavioural addiction.