Radiogenic heat production is a physical parameter crucial to properly estimating lithospheric temperatures and properly understanding processes related to the thermal evolution of the Earth. Yet heat production is, i...Radiogenic heat production is a physical parameter crucial to properly estimating lithospheric temperatures and properly understanding processes related to the thermal evolution of the Earth. Yet heat production is, in general, poorly constrained by direct observation because the key radiogenic elements exist in trace amounts making them difficulty image geophysically. In this study, we advance our knowledge of heat production throughout the lithosphere by analyzing chemical analyses of 108,103 igneous rocks provided by a number of geochemical databases. We produce global estimates of the average and natural range for igneous rocks using common chemical classification systems. Heat production increases as a function of increasing felsic and alkali content with similar values for analogous plutonic and volcanic rocks. The logarithm of median heat production is negatively correlated(r^2=0.98)to compositionally-based estimates of seismic velocities between 6.0 and 7.4 km s^(-1), consistent with the vast majority of igneous rock compositions. Compositional variations for continent-wide models are also well-described by a log-linear correlation between heat production and seismic velocity. However, there are differences between the log-linear models for North America and Australia, that are consistent with interpretations from previous studies that suggest above average heat production across much of Australia. Similar log-linear models also perform well within individual geological provinces with^1000 samples. This correlation raises the prospect that this empirical method can be used to estimate average heat production and natural variance both laterally and vertically throughout the lithosphere. This correlative relationship occurs despite a direct causal relationship between these two parameters but probably arises from the process of differentiation through melting and crystallization.展开更多
Using the perturbation method, we theoretically study the spin current and its heat effect in a multichannel quantum wire with Rashba spin-orbit coupling. The heat generated by the spin current is calculated. With the...Using the perturbation method, we theoretically study the spin current and its heat effect in a multichannel quantum wire with Rashba spin-orbit coupling. The heat generated by the spin current is calculated. With the increase of the width of the quantum wire, the spin current and the heat generated both exhibit period oscillations with equal amplitudes. When the quantum-channel number is doubled, the oscillation periods of the spin current and of the heat generated both decrease by a factor of 2. For the spin current js,xy, the amplitude increases with the decrease of the quantum channel; while the amplitude of the spin current js,yx remains the same. Therefore we conclude that the effect of the quantum-channel number on the spin current js,xy is greater than that on the spin current js,yx. The strength of the Rashba spin-orbit coupling is tunable by the gate voltage, and the gate voltage can be varied experimentally, which implies a new method of detecting the. spin current. In addition, we can control the amplitude and the oscillation period of the spin current by controlling the number of the quantum channels. All these characteristics of the spin current will be very important for detecting and controlling the spin current, and especially for designing new spintronic devices in the future.展开更多
The industrial biomass combustor of Halla food factory in Thailand was designed for drying tuna fish product. The purpose of this paper needed to present the design of a factory combustor for producing heat in the dry...The industrial biomass combustor of Halla food factory in Thailand was designed for drying tuna fish product. The purpose of this paper needed to present the design of a factory combustor for producing heat in the drying process by thermal energy from biomass fuel combustion to reduce the investment cost. A drying chamber was made from four concrete walls in the rectangular volume of 4.7 × 4.7 × 2.5 m3 for drying tuna fishes that sliced to small pieces of around 2,680 kg fresh tuna. The hot air tube in the combustor was used for driving hot air to dry fishes in the drying chamber. Heat from acacia wood burning in the combustor with the consumption rate of 50.1 kg/h was transferred by the hot air. The design result was calculated for thermal energy and the efficiency of around 200 kW, and 32%, respectively in the case of 0.62 m3/s hot air flow rate that circulation between the combustor and the drying chamber. The experimental result shows that the moister content of 78.9%wb was decreased to around 13.8%wb in 5 days without petroleum fuel. The drying temperature was controlled at 70℃ continuously for reducing hard containing, and the closed loop tube design for the less of BaP (benzo (a) pyrene) from combustion smoking of the drying industrial process.展开更多
Needle coke is the starting material for manufacture of premium graphite electrode,which at present cannot be produced by SINOPEC and even other domestic refining enterprises so that the carbon producing plants inside...Needle coke is the starting material for manufacture of premium graphite electrode,which at present cannot be produced by SINOPEC and even other domestic refining enterprises so that the carbon producing plants inside China have to import a significant amount of high-quality needle coke every year.展开更多
Although most fishes are ectothermic,some,including tuna and billfish,achieve endothermy through specialized heat producing tissues that are modified muscles.How these heat producing tissues evolved,and whether they s...Although most fishes are ectothermic,some,including tuna and billfish,achieve endothermy through specialized heat producing tissues that are modified muscles.How these heat producing tissues evolved,and whether they share convergent molecular mechanisms,remain unresolved.Here,we generated a high-quality genome from the mackerel tuna(Euthynnus affinis)and investigated the heat producing tissues of this fish by single-nucleus and bulk RNA sequencing.Compared with other teleosts,tuna-specific genetic variation is strongly associated with muscle differentiation.Single-nucleus RNA-seq revealed a high proportion of specific slow skeletal muscle cell subtypes in the heat producing tissues of tuna.Marker genes of this cell subtype are associated with the relative sliding of actin and myosin,suggesting that tuna endothermy is mainly based on shivering thermogenesis.In contrast,cross-species transcriptome analysis indicated that endothermy in billfish relies mainly on nonshivering thermogenesis.Nevertheless,the heat producing tissues of the different species do share some tissue-specific genes,including vascular-related and mitochondrial genes.Overall,although tunas and billfishes differ in their thermogenic strategies,they share similar expression patterns in some respects,highlighting the complexity of convergent evolution.展开更多
It was not until the winter of 2017 that Dong Jianli felt the heat produced by a nuclear reactor up close, even though she had worked at the China Institute of Atomic Energy (CLAD for more than a decade. From Novembe...It was not until the winter of 2017 that Dong Jianli felt the heat produced by a nuclear reactor up close, even though she had worked at the China Institute of Atomic Energy (CLAD for more than a decade. From November 20 to 28, 2017, the heat emanating from the radiators in her office was being generated by a nuclear reactor, a first in the 67-year history of CIAE, China's first nuclear research arm.展开更多
基金supported by a University of Adelaide summer research scholarship as part of this work
文摘Radiogenic heat production is a physical parameter crucial to properly estimating lithospheric temperatures and properly understanding processes related to the thermal evolution of the Earth. Yet heat production is, in general, poorly constrained by direct observation because the key radiogenic elements exist in trace amounts making them difficulty image geophysically. In this study, we advance our knowledge of heat production throughout the lithosphere by analyzing chemical analyses of 108,103 igneous rocks provided by a number of geochemical databases. We produce global estimates of the average and natural range for igneous rocks using common chemical classification systems. Heat production increases as a function of increasing felsic and alkali content with similar values for analogous plutonic and volcanic rocks. The logarithm of median heat production is negatively correlated(r^2=0.98)to compositionally-based estimates of seismic velocities between 6.0 and 7.4 km s^(-1), consistent with the vast majority of igneous rock compositions. Compositional variations for continent-wide models are also well-described by a log-linear correlation between heat production and seismic velocity. However, there are differences between the log-linear models for North America and Australia, that are consistent with interpretations from previous studies that suggest above average heat production across much of Australia. Similar log-linear models also perform well within individual geological provinces with^1000 samples. This correlation raises the prospect that this empirical method can be used to estimate average heat production and natural variance both laterally and vertically throughout the lithosphere. This correlative relationship occurs despite a direct causal relationship between these two parameters but probably arises from the process of differentiation through melting and crystallization.
文摘Using the perturbation method, we theoretically study the spin current and its heat effect in a multichannel quantum wire with Rashba spin-orbit coupling. The heat generated by the spin current is calculated. With the increase of the width of the quantum wire, the spin current and the heat generated both exhibit period oscillations with equal amplitudes. When the quantum-channel number is doubled, the oscillation periods of the spin current and of the heat generated both decrease by a factor of 2. For the spin current js,xy, the amplitude increases with the decrease of the quantum channel; while the amplitude of the spin current js,yx remains the same. Therefore we conclude that the effect of the quantum-channel number on the spin current js,xy is greater than that on the spin current js,yx. The strength of the Rashba spin-orbit coupling is tunable by the gate voltage, and the gate voltage can be varied experimentally, which implies a new method of detecting the. spin current. In addition, we can control the amplitude and the oscillation period of the spin current by controlling the number of the quantum channels. All these characteristics of the spin current will be very important for detecting and controlling the spin current, and especially for designing new spintronic devices in the future.
文摘The industrial biomass combustor of Halla food factory in Thailand was designed for drying tuna fish product. The purpose of this paper needed to present the design of a factory combustor for producing heat in the drying process by thermal energy from biomass fuel combustion to reduce the investment cost. A drying chamber was made from four concrete walls in the rectangular volume of 4.7 × 4.7 × 2.5 m3 for drying tuna fishes that sliced to small pieces of around 2,680 kg fresh tuna. The hot air tube in the combustor was used for driving hot air to dry fishes in the drying chamber. Heat from acacia wood burning in the combustor with the consumption rate of 50.1 kg/h was transferred by the hot air. The design result was calculated for thermal energy and the efficiency of around 200 kW, and 32%, respectively in the case of 0.62 m3/s hot air flow rate that circulation between the combustor and the drying chamber. The experimental result shows that the moister content of 78.9%wb was decreased to around 13.8%wb in 5 days without petroleum fuel. The drying temperature was controlled at 70℃ continuously for reducing hard containing, and the closed loop tube design for the less of BaP (benzo (a) pyrene) from combustion smoking of the drying industrial process.
文摘Needle coke is the starting material for manufacture of premium graphite electrode,which at present cannot be produced by SINOPEC and even other domestic refining enterprises so that the carbon producing plants inside China have to import a significant amount of high-quality needle coke every year.
基金supported by the National Natural Science Foundation of China(32122021)the National Key Research and Development Program of China(2022YFC3400300)+1 种基金the 1000 Talent Project of Shaanxi Province to Q.Q.and K.W.,the Fundamental Research Funds of Northwestern Polytechnic Universitythe Open Foundation from Marine Sciences in the First-Class Subjects of Zhejiang(OFMS011)。
文摘Although most fishes are ectothermic,some,including tuna and billfish,achieve endothermy through specialized heat producing tissues that are modified muscles.How these heat producing tissues evolved,and whether they share convergent molecular mechanisms,remain unresolved.Here,we generated a high-quality genome from the mackerel tuna(Euthynnus affinis)and investigated the heat producing tissues of this fish by single-nucleus and bulk RNA sequencing.Compared with other teleosts,tuna-specific genetic variation is strongly associated with muscle differentiation.Single-nucleus RNA-seq revealed a high proportion of specific slow skeletal muscle cell subtypes in the heat producing tissues of tuna.Marker genes of this cell subtype are associated with the relative sliding of actin and myosin,suggesting that tuna endothermy is mainly based on shivering thermogenesis.In contrast,cross-species transcriptome analysis indicated that endothermy in billfish relies mainly on nonshivering thermogenesis.Nevertheless,the heat producing tissues of the different species do share some tissue-specific genes,including vascular-related and mitochondrial genes.Overall,although tunas and billfishes differ in their thermogenic strategies,they share similar expression patterns in some respects,highlighting the complexity of convergent evolution.
文摘It was not until the winter of 2017 that Dong Jianli felt the heat produced by a nuclear reactor up close, even though she had worked at the China Institute of Atomic Energy (CLAD for more than a decade. From November 20 to 28, 2017, the heat emanating from the radiators in her office was being generated by a nuclear reactor, a first in the 67-year history of CIAE, China's first nuclear research arm.