Internal Energy Release Research Articles

Acoustic emission monitoring for engineered barriers in nuclear waste disposal

To safely dispose of nuclear waste in underground facilities, engineered barrier systems are needed to seal shafts and galleries. The material used in these barriers must be adapted to the host rock parameters. Shrinking and cracking must be avoided to provide a barrier with almost zero permeability. For repositories in salt rock environments, several types of salt concrete (SC) are used. Within the project SealWasteSafe, we compared the performance of an innovative alkali-activated material (AAM) with standard SC in their hydration and hardening phase. To monitor the microstructural changes within the two materials SC and AAM, acoustic emission (AE) signals have been recorded for up to ~250 days on 340-liter-cubic specimens. The phenomenon of AE is defined as the emission of elastic waves in materials due to the release of localized internal energy. Such energy release can be caused by the nucleation of micro-fracture, e.g. in concrete while curing or when exposed to load. The occurrence of AE events gives first rough indications of microstructural changes and potentially occurring cracking and thus, provides insights for structural health monitoring (SHM). The results show, that for the first 28 days after casting, less AE activity was detected in the AAM compared to SC. After 61 days, in the AAM material, the number of AE events exceeded those observed in the SC. However, the majority of the AE detected in AAM was related to surface effects, and not to microstructural changes within the matrix. Additionally, the source location analysis indicated, that despite lower activity in SC, we observed some clustering of the events. In contrast, in AAM, the activity inside the specimen is randomly distributed over the whole volume. The monitoring results help to estimate the material’s sealing properties which are crucial to assess their applicability as sealing material for engineered barriers.

Energy transfer and release during the fracture of UD fiber-reinforced thermoplastic composites

This study delves into the complex dynamics of energy transfer and release during the fracture of unidirectional (UD) fiber-reinforced thermoplastic composites. Conducted through meticulous experimental observations and rigorous energy analysis, the research presents groundbreaking conclusions on the fracture toughness and energy conversion efficiency of UD carbon fiber composites under various loading conditions. A prominent focus is on how these mechanical properties are intricately linked to the sample’s fiber orientation angles and the external conditions applied during testing.The work employed tapered double cantilever beam (TDCB) as the far-field boundary to investigate the energy changes, transfer, and conversion processes during the crack propagation of unidirectional fiber reinforced thermoplastics (UDFRTPs) structures. It was found that throughout the entire propagation process, blunt extension occurs first followed by inertial extension. This is because in the initial stage of crack propagation, the stored elastic energy in the structure is relatively small, making the crack tip prone to blunting. This continuous blunting impedes the release of internal strain energy in the structure, with blunt extension accounting for a very small proportion of the entire fracture process. When the internal strain energy in the structure continues to increase to a certain extent, the blunting of the crack tip cannot prevent the release of a large amount of elastic energy inside the structure. At the same time, the excess released strain energy converts into kinetic energy and continually impacts the blunted region at the crack tip. At this point, the propagation transitions into the inertial extension stage, which occupies a significant portion of the entire fracture process.

Spontaneous In-Source Fragmentation Reaction Mechanism and Highly Sensitive Analysis of Dicofol by Electrospray Ionization Mass Spectrometry.

Although dicofol has been widely banned all over the world as a kind of organochlorine contaminant, it still exists in the environment. This study developed a high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS) detection technique for dicofol, an environmental pollutant, for the first time using in-source fragmentation. The results confirmed that m/z 251 was the only precursor ion of dicofol after in-source fragmentation, and m/z 139 and m/z 111 were reasonable product ions. The main factors triggering the in-source fragmentation were the H+ content and solution conductivity when dicofol entered the mass spectrometer. Density functional theory can be used to analyze and interpret the mechanism of dicofol fragmentation reaction in ESI source. Dicofol reduced the molecular energy from 8.8 ± 0.05 kcal/mol to 1.0 ± 0.05 kcal/mol, indicating that the internal energy release from high to low was the key driving force of in-source fragmentation. A method based on HPLC-MS/MS was developed to analyze dicofol residues in environmental water. The LOQ was 0.1 μg/L, which was better than the previous GC or GC-MS methods. This study not only proposed an HPLC-MS/MS analysis method for dicofol for the first time but also explained the in-source fragmentation mechanism of compounds in ESI source, which has positive significance for the study of compounds with unconventional mass spectrometry behavior in the field of organic pollutant analysis and metabonomics.

ФУНДАМЕНТАЛІЗАЦІЯ ОСВІТИ В ЇЇ ПРОЄКТИВНОСТІ – ТРАНССПЕКТИВА ВІД МІКРОСВІТУ ДО МАКРОСВІТУ

The article emphasises that the fundamentalisation of general secondary education and the range of pedagogical education that provides it, the awakening of the profile of the individual and the organization of specialized cooperation of regions along with modernizing the education system with a view to the noosphere perspective is an urgent task today. The main direction of development of pedagogical consciousness of our time is its scientific development, noosphere modernization of the educational system with a willingness to educate and develop a true man – synchronous biosphere, the chronotope of which must have a higher degree of release of internal energy – noosphere. The authors identify the key ideas of noosphere humanism in Ukraine as follows: designing the future as part of a threefold educational goal-ideal “welfare state – civil society – environmental thinking” should begin from the education system of the region as a purely natural area with state, regional and school components of educational content (academic and applied components); Ukraine’s education system should be guided by the framework law on education and regional educational achievements – regional educational constitutions, and the school component of educational content is developed on the basis of regulations of an educational institution, created and coordinated by the community for individual development; the path of education begins as a psychological and pedagogical problem in the depths of personality, proceeds as a polymorphism of interests (amorphous – broad – core) in the direction of opportunities for their implementation in social work as a profile; the beginnings of cognition are fused by the correct immersion of the individual in nature, in life - the conditions of the ecological trail of the region with points of contemplation and study of the environment with the possibility of comparison with the ideal (tend to deepen educational material, decompose the problem of improving quality of life); the educational environment develops on a democratic principle, where the spirit of law operates, the balance of all branches of government at all levels of the organization, respect for the individual; noosphere profile education realises the synthesis of natural and historical process, takes into account the pace of formation of global democratic social relations as a synthesis of labour, reason and scientific thought related to the religious context in the interests of civilisation; consciousness is the result of evolution, its origins are of geological origin, personal embodiment and collective application: direct, indirect. The human world largely begins in itself, is constructed by it and “settles” in it at the final stage, so the profile of learning in advance should be said as the length along which the energy of life moves; it is necessary to re-motivate human life as the immortality of the individual in the cosmos, because knowledge of the possible, awareness of the necessary, scientific justification of the conscious – one common idea of the people of the planet Earth; education is the most effective means by which a human becomes a Person, the shortest path to civilisation. The authors predict the future projective function of education in Ukraine in relation to human life (essentially compensatory).

Experimental Study on Work of Adsorption Gas Expansion After Coal and Gas Outburst Excitation

Coal and gas outburst is an extremely complex dynamic phenomenon of mine gas, which is mainly manifested in a very short time. A large amount of coal and rock are thrown out from the coal body to the mining space and accompanied by a large volume of high-pressure gas. In the process of coal and gas outburst, the internal energy consumption of gas is composed of two parts: one is used to throw out broken coal and rock mass, and the other is used to pulverize broken coal. In this article, from the perspective of energy dissipation, the experiment of broken coal ejection with different coal particle sizes, different adsorption gas, and pressure is studied. The characteristics of coal ejection are studied and analyzed, and the proportion of adsorbed gas participating in the outburst work is quantitatively analyzed. The results show that after outburst excitation, residual gas will continue to desorb and work on outburst until the power is insufficient to throw coal body; compared with air, CO2 gas has a stronger ability to work on the outburst, and the outburst coal is thrown far away, and the pulverization effect is stronger. Through the energy analysis in the process of outburst, the results show that when the particle size of the coal sample is consistent, the greater the outburst pressure is, the larger the desorption amount of the adsorbed gas is, and the larger the volume involved in the outburst work is. When the test gas is consistent with the outburst pressure, the gas desorption amount of the small-size coal sample is more, the desorption gas has a stronger ability to work on the outburst, and the proportion of participating in outburst work is higher. The crushing degree of coal plays an important role in the expansion and release of gas internal energy.

Modification of the multiphase shape memory composites with functionalized graphene nanoplatelets: enhancement of thermomechanical and interfacial properties

Ameliorating the mechanical and thermomechanical properties of the shape memory polymers (SMPs) make them an important class of materials for new-age applications ranging from aerospace, electronics, and marine. To show the more recent attempts proof-of-concept in designing the SMPs with higher mechanical and thermomechanical properties, herein we had designed the multiscale shape memory hybrid composites (SMHCs) having known composition of functionalized graphene nanoplatelets (fGNPs) through dispersing the fGNPs uniformly using ultrasonication in shape memory epoxy polymer. Subsequently, hybrid composites were prepared through impregnation of carbon fiber in the fGNP ∼ epoxy solution. Mechanical and thermomechanical characterizations were performed to evaluate the effect of the fGNPs within the SMHC. Significant improvement in the mechanical and thermomechanical properties were achieved in the SMHC with amine functionalized fGNP compared with the carboxy functionalized fGNP and non-functionalized epoxy polymer. Compared with the unmodified carbon fiber reinforced polymer composites, SMHC with 0.4 and 0.6 wt% amine fGNP improved by 19.7% and 33.2%, whereas 5.9% and 17.4% by carboxyl fGNP. Morphological study indicated the improvement of wettability of carbon fiber and interfacial bonding between the fiber and matrix. The recovery of the modified polymer composites into the original shape primarily occurred due to the gradual release of internal energy harnessed in the frozen and active phase of the polymer network. Due to the incorporation of nanofillers, the molecular kinetic energy of the reversible active phase increases, which intensifies the micro-Brownian motion. Thereby, the recovery stage was achieved due to the return of the frozen phase to the disoriented entropy condition. The addition of nanoparticles increases the cross-linking, which in turn increases the volume of the frozen phase. Hence, higher volume of frozen phase would hamper the recovery of the samples in its original shape, resulting in the lower shape fixity. However, the shape memory parameters of shape fixity and shape recovery evaluated with the heat activation bending did not degraded significantly and remained ∼95 ± 2% and ∼96 ± 1%, respectively.

The Onset of a Substorm and the Mating Instability

AbstractThe paper underlines the view that the appearance of beading and its nonlinear growth in the onset arc occurs independently from the onset of reconnection in the tail at about 20 RE. Both events follow from an extreme thinning of the central current sheet of the tail at the end of the growth phase. Subsequently, we concentrate on the processes connected with the onset arc breakup. Its origin lies in the instability of a high‐beta plasma layer building up at the outer boundary of the dipolar magnetosphere during the substorm growth phase, the growth phase arc (GPA) being the ionospheric trace. The observation of auroral streamers triggering the onset arc instability lets us analyze what is known about auroral streamers with strong support from high‐resolution videos of two substorm onsets. We conclude that they may be low‐entropy content bubbles with a balanced field‐aligned current system, framing a flow channel. However, there are unresolved questions. The visible streamer is identified as an Alfvénic arc. In searching for a mechanism by which a streamer bubble lining up along the GPA can trigger the instability, we are led to the recognition that an entirely new non‐MHD process must be at work. Taking also into account the surprising fact that the beads are moving oppositely to the convection in GPA and auroral streamer, we postulate the appearance of a new current system in the gap between the two. What happens can be described as the mating of two current sheets, which were completely separated before. It breaks the stability of the high‐beta plasma layer and channels the release and conversion of free internal energy. For this reason, we name the process mating instability. A physical analysis of this process shows consistency with detailed features exhibited by the two videos

More on methods to measure the energetics of lithium ion batteries in thermal runaway

Experiments have been conducted on a variety of lithium ion batteries to measure their energy output in thermal runaway. Techniques were developed to measure the internal energy release as decomposition of the battery takes place, and combustion energy that can arise from ignited battery gases released in runaway. A nitrogen bomb calorimeter was designed, constructed and utilized to measure the internal energy in runaway. Three techniques were examined for measuring the combustion energy: (1) the Cone Calorimeter, (2) the Oxygen Bomb, and (3) the using a Gas Chromatograph to measure combustion species. The results from these measurement techniques are discussed and compared to the literature for similar batteries. Results generally show for 18650 batteries that the energies in runaway depend on chemistry, decomposition tends to increase with the SOC and can exceed its electric energy by 2-times, while combustion energy can reach 6-times.

Meridional Circulation with Latitude Bands of Long-Lived Cyclones in Jupiter’s Convective Atmosphere

Mayr et al. [1] proposed that the vertical velocities in the global scale meridional circulation can produce distinct latitude bands where Jovian vortices like the white and brown are observed, and we present here a brief review of the mechanism. The observed life times of the ovals are much longer than the estimated spin-down times, which indicates that the vortices must be sustained through the release of internal energy. Like Jupiter’s Great Red Spot (GRS), the white/brown ovals are treated like terrestrial hurricanes or cyclones, which are generated by convection. The planetary energy Jupiter emits is transferred by convection, and under this condition the upward motions in the meridional circulation, around the equator for example, release energy from below and decrease the convective instability to suppress the formation of cyclones. But the downward motions in the circulation, near 20° latitude for example, carry energy down so that the convective instability is amplified to produce a dynamical environment that is favorable for the development of cyclones like the GRS and white/brown ovals. This picture is supported by an analysis of results from a numerical model of Jupiter’s alternating jets (Chan and Mayr [2]). Generated by alternating vertical winds in the meridional circulation, the vertical temperature variations reveal distinct latitude bands with enhanced convective instability, most prominent at high latitudes where long-lived circumpolar cyclones are observed from the Juno spacecraft.

Methods and results of determining the impurity gas amount in ceramic fuel

An issue of estimating the impurity gas amount in fresh ceramic nuclear fuel is discussed from the point of view of their possible influence on parameters of in-pile experiments simulating a severe accident with core melting. A method based on measuring the pressure and temperature of gas in a closed cavity where fuel is fast melted is proposed and experimentally tested under in-pile experiment conditions. The fuel was melted due to internal energy release in the central experimental channel of the research impulse graphite reactor (IGR) during implementation of a controlled neutron impulse.

Experimental Study on Influence of Borehole Arrangement on Energy Conversion and Acoustic Characteristics of Coal-Like Material Sample

This paper examines the effects of borehole arrangement on the failure process of coal-like materials based on its energy conversion and acoustic characteristics from the perspectives of energy, AE energy, AE spectrum, and frequency band. Findings from the study revealed that the presence of borehole can significantly reduce the conversion ratio and growth rate of elastic energy during the loading of coal-like material sample and delay the release of internal energy of the sample. Also, it can reduce the frequency band energy of the main frequency of acoustic emission signal but has little effect on the size and richness of the peak frequency of acoustic emission signal. The practice that makes drilling diameter and depth increase stepwise can minimize the elastic energy conversion ratio, the growth rate, and the main frequency band energy of acoustic emission signal of coal-like material sample and postpone the internal energy release of the sample to the greatest extent, so as to enrich the richness of the secondary frequency of acoustic emission signal. The results of this study have certain guiding significance for the layout of pressure relief boreholes in the production process of coal mines.

Experimental Study on Effects of Loading Rate and Sample Size on the Mechanical and Failure Characteristics of Mudstone

In this study, to explore the effects of the loading rate and sample sizes on the mechanical properties of rock, uniaxial compression experiments are conducted for mudstone with two different sample sizes and loading rates to obtain its mechanical properties and failure characteristics. Results show that mechanical parameters such as the compressive strength and elastic modulus obtained at a loading rate of 0.01 mm/s are higher than those obtained at a loading rate of 0.001 mm/s. Moreover, the mechanical parameters of rock samples in group A (Φ50 × 100 mm2) are higher than those in group B (Φ25 × 50 mm2) at the loading rate of 0.01 mm/s, whereas it is the opposite at the 0.001 mm/s loading rate. At the same loading rate, the strain of rock samples in group A is slightly higher than that of group B in the fracture compaction stage, while the difference is trivial for rock samples with the same size under different loading rates. The dispersion degree of the stress–strain curve under the 0.001 mm/s loading rate is greater than that under the 0.01 mm/s loading rate for both groups, and the local failure characteristics can be observed from the pre-peak curve. A positive and logarithmic relationship is observed between the pre-peak strain energy and compressive strength. Under the 0.01 mm/s loading rate, the rock samples show only shear failure, whereas the mixed shear-splitting failure is observed under the 0.001 mm/s loading rate with extensive fracture development and multiple failure surfaces, indicating that the internal energy release is more stable and completed.

Experimental Study on Energy Consumption of Rock Cutting under Different Groove Geometry

Abstract The Polycrystalline Diamond Compact (PDC) cutter is a kind of rock breaking tool that is widely used in oil and gas exploitation. PDC cutter directly contacts with the rock during the process of the rock cutting. Therefore, it is of great significance to investigate the rock breaking mechanism of the PDC cutter to improve the rock breaking efficiency. This article sets up a test bench of rock cutting, which consists of a single cutter, high-speed cameras, and several data collectors, to monitor the cutting force, mechanical specific energy, energy dissipation, and the chip formation process. The results show that a frequent fluctuation of the value of the tangential force is related to the fly leaping phenomenon and particle size of debris. The ratio coefficient of the cross section describes the relations of energy dissipation between different sections. While changing the distribution density of the PDC cutter on the drilling bit, a minimum value of rock-breaking specific work will appear, and the rock breaking efficiency can be improved. The arc length back virtual work and the virtual crushing work express the storage and release of rock internal energy, which can explain the fracture phenomenon from the aspect of energy dissipation.

Development of the model to determine the fuel temperature field in a two-dimensional problem statement

Water-cooled water-moderated reactors (VVER) are widely used at Russian nuclear power plants. The VVER reactor core is formed by fuel assemblies consisting of fuel rods. The fuel in fuel rods is uranium dioxide. The safety of the reactor operation is ensured through stringent requirements for the maximum nuclear fuel temperature. Calculation of temperature fields within the reactor core requires associated problems to be solved to determine the internal energy release in fuel based on neutronic characteristics. Dedicated software for such calculations is not available to a broad range of users. At the present time, there are numerical thermophysical modeling packages available for training or noncommercial applications which are used extensively, including Elcut, Flow Vision, Ansys Fluent, and Comsol Multiphysics. Verification of the obtained results is becoming an important issue in building models using these calculation packages. An analytical solution was obtained as part of the study for the fuel temperature field determination. A program was developed in MathCAD based on this solution. A model was developed in Comsol Multiphysics to determine the fuel temperature field with constant thermophysical properties in a two-dimensional problem statement. The numerical model was verified using the analytical solution. The influence of the number of the grid nodes on the solution accuracy was established. The analytical solution can be used to determine the fuel temperature field at any radial coordinate of the reactor. The temperature field determination model developed in MathCAD can be used to verify numerical models of the fuel temperature field determination developed in dedicated packages.

Internal electromagnetic waves, energy trapping, and energy release in simple time-domain simulations of single particle scattering.

During the decay phase of the interaction of a femto-second Gaussian pulse with a single spherical particle, the presence of quasi-periodic short oscillatory bursts of electromagnetic energy at points in the near field outside the particle have been observed in three-dimensional simulations. Analogous behavior can be very easy produced and understood in simple one-dimensional scattering calculations. In two dimensions the situation immediately becomes more complicated and interesting. Here we discuss results from two-dimensional pseudo-spectral time-domain simulations of scattering from circular, elliptical, and hexagonal particles with the real index of refraction m = 1.3. Our focus is on how energy initially trapped within a particle after interaction with an incident Gaussian pulse is released over time, and we show two kinds of events that can result in “bursts” of energy release from the particles: (i) the coalescence of counter-propagating wave-packet-like electromagnetic field structures that have maximum amplitude near the surface of the particle, and (ii) encounters of individual packets with surface regions of high curvature. The coalescence events in the circular case show the dynamical origin of a two-dimensional form of “photonic nanojet.” The two-dimensional simulations make clear the reason for quasi-periodic intermittent bursts at fixed near-field points outside the particle. Examination of field evolution shows that distinct near-surface internal field maxima, ostensibly the “source” of the emission bursts, are in fact inter-connected by caustic-like internal field structures that extend throughout the particle and have complex time evolution. The revealed intricacy of these connections suggests that understanding the origins of pulsed emissions in three dimensions, even for simple particle geometries, may be quite challenging.

SUSTAINABLE BIO-COMPOSITE ITS MANUFACTURING PROCESSES AND APPLICATIONS

The biocomposite materials which serve for present nation or civilization without affecting our future generation is called as sustainable biocomposite i.e., it does not affect our environment and save our environment from toxic and hazardous effect. The sources and production of the raw materials, material Processing, the service-life of the product and waste management should be evaluated in terms of energy, chemical consumption, emissions of gaseous materials, toxicology upon use and disposal of a biocomposite are considered as sustainable bio-composites. This can be formed by different manufacturing process like filament winding, lay up method, extrusion moulding, Injection moulding, compression moulding, Resin transfer moulding, Sheet moulding compound etc. Sustainable biocomposite have several advantages like light weight, high specific stiffness, high strength, low electrical conductivity, easily bondable, good fatigue resistance, internal energy storage and release, low thermal expansion, easily moulded to complex and design flexibility etc. These biocomposite have huge applications in several fields like in the field of domestic sector, building materials, aerospace industry, circuit boards and automobile applications. It supports our sustainable environment by using natural fibres like jute, hemp, sisal, knead, flax etc. which is the cause of biodegradation and can also be used in the industrial scale. It not only saves our environment but also made our life easier and more comfortable.

Coronal Flux Rope Catastrophe Associated With Internal Energy Release

AbstractMagnetic energy during the catastrophe was predominantly studied by the previous catastrophe works since it is believed to be the main energy supplier for the solar eruptions. However, the contribution of other types of energies during the catastrophe cannot be neglected. This paper studies the catastrophe of the coronal flux rope system in the solar wind background, with emphasis on the transformation of different types of energies during the catastrophe. The coronal flux rope is characterized by its axial and poloidal magnetic fluxes and total mass. It is shown that a catastrophe can be triggered by not only an increase but also a decrease of the axial magnetic flux. Moreover, the internal energy of the rope is found to be released during the catastrophe so as to provide energy for the upward eruption of the flux rope. As far as the magnetic energy is concerned, it provides only part of the energy release, or even increases during the catastrophe, so the internal energy may act as the dominant or even the unique energy supplier during the catastrophe.

Propagation Characteristics of Acoustic Emission in Plate Structure with Various Materials and Multilayer Medium

Acoustic emission signal is a kind of elastic wave which is caused by the release of internal energy of materials when the structure changes. The propagation characteristics of acoustic emission is important to the testing technology of a structure by acoustic emission signal. The finite element method is introduced to analyze elastic wave propagation in plate structure in the article, which mainly contains the discretization techniques of the area and time domain. The structure plate with different materials ,style and coating metal are selected in finite element simulation, the displacement contours and wave curve resulted from simulation are used to analyze the interface reflection, refraction and diffraction process as well as the wave type conversion in different medium of the elastic wave propagation . The mechanical pencil lead fracture experiment is done to verify the transient simulation of elastic wave propagation in plate structure.

Negative stiffness induced by shear along wavy interfaces

The extension of an elastic body almost always leads to mechanical tension in the stretching direction. Here, we report an unusual phenomenon of global mechanical compression in the stretching direction of an elastic body containing sinusoidal wavy interfaces. When the elastic body with a wavy interface is subjected to tensile loading, the local stress state along the interface is mixed-mode. Finite element simulations show that the resistance of the interface to shear-slip locks the interface together, and generates a moment couple which rotates the interface. Once the local adhesive shear strength of the interface is reached, the interface slips and separates. Then, the rotated interface triggers a restoring moment couple which releases the stored elastic energy. The structure subsequently undergoes global compression in the stretching direction until the interface completely separates. This moment-couple-induced internal energy storage and release mechanism leads to a material structure that exhibits high initial strength and toughness, followed by post-peak compliant softening with negative stiffness. This structural negative stiffness behavior is closely-tied with the ability of the interface to store and release energy by rotation, and is also exhibited by polycrystalline structures where grain rotation is possible.

The Distribution and Composition Characteristics of Siliceous Rocks from Qinzhou Bay‐Hangzhou Bay Joint Belt, South China: Constraint on the Tectonic Evolution of Plates in South China

The Qinzhou Bay-Hangzhou Bay joint belt is a significant tectonic zone between the Yangtze and Cathaysian plates, where plentiful hydrothermal siliceous rocks are generated. Here, the authors studied the distribution of the siliceous rocks in the whole tectonic zone, which indicated that the tensional setting was facilitating the development of siliceous rocks of hydrothermal genesis. According to the geochemical characteristics, the Neopalaeozoic siliceous rocks in the north segment of the Qinzhou Bay-Hangzhou Bay joint belt denoted its limited width. In comparison, the Neopalaeozoic Qinzhou Bay-Hangzhou Bay joint belt was diverse for its ocean basin in the different segments and possibly had subduction only in the south segment. The ocean basin of the north and middle segments was limited in its width without subduction and possibly existed as a rift trough that was unable to resist the terrigenous input. In the north segment of the Qinzhou Bay-Hangzhou Bay joint belt, the strata of hydrothermal siliceous rocks in Dongxiang copper-polymetallic ore deposit exhibited alternative cycles with the marine volcanic rocks, volcanic tuff, and metal sulphide. These sedimentary systems were formed in different circumstances, whose alternative cycles indicated the release of internal energy in several cycles gradually from strong to weak.