Although a variety of precursors have been proposed for the formation of high molecular weight hydro-carbons (HMWHCs) in crude oil, their precise origin re-mains elusive. Quantitative studies of macrocrystalline wax a...Although a variety of precursors have been proposed for the formation of high molecular weight hydro-carbons (HMWHCs) in crude oil, their precise origin re-mains elusive. Quantitative studies of macrocrystalline wax and microcrystalline wax content of source rock extracts from the Damintun depression, Liaohe Basin, a typical high wax producing area, coupled with microscopical maceral composition studies and pyrolysis-GC analysis indicate that oil shale enriched in lacustrine biomass makes a primary contribution to wax in oil. The main precursors of high wax oil are lacustrine alginites and their amorphous matrix, which are highly aliphatic in nature and have high genera-tive potential for HMWHCs. Wax generation efficiency could be affected by organic material abundance and matur-ity. The high abundance and low maturity of organic mate-rial are favorite for the formation of high quantity of wax, which declines with decreasing organic abundance and in-creasing thermal maturity. This suggests that wax is derived from organic-rich lacustrine biomass at early stages of maturation (RO = 0.4%—0.7%). Although the contribution of high plant cuticular wax and sporopollen cannot be ruled out, lacustrine biomass is more important in the formation of high wax oil.展开更多
Wearable body sensor nodes require massive data transmission under limited energy.However,it suffers from drastically varying channel loss,which limits its energy efficiency in practical scenarios.This paper presents ...Wearable body sensor nodes require massive data transmission under limited energy.However,it suffers from drastically varying channel loss,which limits its energy efficiency in practical scenarios.This paper presents a power-driven body-channel transceiver(TRX),whose power consumption can be adaptively tuned against varying channel loss.An out-band programmable gain amplifier(PGA)is proposed to save power and generate a quasi-linear correlation between PGA gain and power.By using the quasi-linear gain-power relationship,we propose an auto gain/power control technique to realize on-demand power consumption.In addition,a differential balanced transmitter is designed to eliminate base-band harmonics in on-off keying modulation and increase the power delivered by the transmitter(TX).The TX and receiver(RX)of the prototype were integrated into 1 chip and fabricated in a 55-nm complementary metal oxide semiconductor process.During the measurement,2 chips were configured as TX and RX,respectively.Both the TX and the RX were wearable,powered by lithium batteries,and attached to the subject’s hands.The prototype achieved a 5.25-Mbps data rate with 16-pJ/bit energy efficiency at a 1.5-m straight-line ground path distance.Furthermore,the proposed TRX maintained stable communication within a 1.5-m distance,while dynamically reducing power consumption.展开更多
文摘Although a variety of precursors have been proposed for the formation of high molecular weight hydro-carbons (HMWHCs) in crude oil, their precise origin re-mains elusive. Quantitative studies of macrocrystalline wax and microcrystalline wax content of source rock extracts from the Damintun depression, Liaohe Basin, a typical high wax producing area, coupled with microscopical maceral composition studies and pyrolysis-GC analysis indicate that oil shale enriched in lacustrine biomass makes a primary contribution to wax in oil. The main precursors of high wax oil are lacustrine alginites and their amorphous matrix, which are highly aliphatic in nature and have high genera-tive potential for HMWHCs. Wax generation efficiency could be affected by organic material abundance and matur-ity. The high abundance and low maturity of organic mate-rial are favorite for the formation of high quantity of wax, which declines with decreasing organic abundance and in-creasing thermal maturity. This suggests that wax is derived from organic-rich lacustrine biomass at early stages of maturation (RO = 0.4%—0.7%). Although the contribution of high plant cuticular wax and sporopollen cannot be ruled out, lacustrine biomass is more important in the formation of high wax oil.
基金supported by the National Key Research and Development Program of China under Grant No.201-9YFB2204500in part by the Natural Science Foundation of China(NSFC)under Grant 61904104.
文摘Wearable body sensor nodes require massive data transmission under limited energy.However,it suffers from drastically varying channel loss,which limits its energy efficiency in practical scenarios.This paper presents a power-driven body-channel transceiver(TRX),whose power consumption can be adaptively tuned against varying channel loss.An out-band programmable gain amplifier(PGA)is proposed to save power and generate a quasi-linear correlation between PGA gain and power.By using the quasi-linear gain-power relationship,we propose an auto gain/power control technique to realize on-demand power consumption.In addition,a differential balanced transmitter is designed to eliminate base-band harmonics in on-off keying modulation and increase the power delivered by the transmitter(TX).The TX and receiver(RX)of the prototype were integrated into 1 chip and fabricated in a 55-nm complementary metal oxide semiconductor process.During the measurement,2 chips were configured as TX and RX,respectively.Both the TX and the RX were wearable,powered by lithium batteries,and attached to the subject’s hands.The prototype achieved a 5.25-Mbps data rate with 16-pJ/bit energy efficiency at a 1.5-m straight-line ground path distance.Furthermore,the proposed TRX maintained stable communication within a 1.5-m distance,while dynamically reducing power consumption.
