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An NFC tag chip employing the ISO/IEC14443-A protocol is developed in SMIC $0.13\mu \text{m}$ EEPROM 2P6M CMOS process, boasting a chip area of $620.03\mu \text{m}\times 567.93\mu \text{m}$ and a power consumption of under $100\mu \text{W}$ . The chip addresses critical issues such as reducing power consumption and minimizing area costs for covering numerous IoT nodes. For a small area of the chip, a specialized ESD protection circuit is proposed, efficiently multiplexing discharge transistors, cross-gate connected rectifiers, limiters for overvoltage protection, and load switch modulators within the chip’s limited space. For power efficiency, a compact $175.44\mu \text{m}\times 32.98\mu \text{m}\,\,18.52\mu \text{A}$ LDO based on the current mirror and current feedback is presented for the DC supply during the 100% ASK modulation. Additionally, an ASK demodulator and a 13.56MHz±kHz clock generator are designed in compact areas of $62.19\mu \text{m}\times 56.06\mu \text{m}$ and $24.76\mu \text{m}\times 13.14\mu \text{m}$ , respectively. These components ensure stable protocol communication with digital circuits and support a 7kb EEPROM, providing a comprehensive solution for NFC-based IoT information collection.

The development and application of various precision electronic devices require a large number of high-precision and low-cost temperature-compensated crystal oscillators (TCXO) to generate frequency references. In order to achieve higher compensation accuracy at lower cost, a new fully integrated analog-TCXO (ATCXO) is proposed in this paper. It uses an innovative temperature-compensated multiplier to generate cubic and quintic voltages. The experimental results show that it can achieve the ultra-high fitting of the frequency-temperature characteristic curve of the crystal. This effectively improves the compensation accuracy of the TCXO. The proposed ATCXO achieves a frequency stability of ± 0.8 ppm in the temperature range of $- 40\,\,^{\circ }\text{C}$ to 95 °C. At the same time, the gain-temperature error of the proposed temperature compensated analog multiplier is $\le 0.13$ dB. This paper is based on SMIC 130 nm process, the core area of the chip is only 0.124 mm2. Multiple modules such as bandgap circuit, n-th power voltage generation circuit, summation circuit, gain control circuit and voltage controlled oscillator using variable capacitor array are integrated.

Objectives: To summarize the clinical characteristics and investigate the efficacy of ethanol embolotherapy in the treatment of chest well arteriovenous malformation (AVM). Treatment-associated complications were also explored.Materials and Methods: Between March 2017 and August 2021, 32 consecutive patients (mean age, 23.7 years; age range, 5–54 years) who underwent ethanol embolotherapy for chest well AVMs under general anesthesia were included in this study. Embolization was performed through a direct puncture, transarterial catheterization, or a combination of the 2 procedures. The mean follow-up duration after the last treatment was 18.0 months (range, 3–42 months). The degree of devascularization on follow-up (assessed using angiography or computed tomography), and the clinical signs and symptoms of AVMs were evaluated as the therapeutic outcomes. The major and minor complications associated with the procedures were recorded.Results: A total of 103 embolization procedures (mean, 3.2; range, 2–7) comprising 101 ethanol embolization and 2 coil embolizations were performed on 32 patients with chest wall AVMs. The AVM nidus was accessed through the transarterial approach alone in 4 patients, by direct puncture in 11, and a combined procedure in 17 patients. Overall, more than 80% of the procedures were performed using the combined approach. Complete AVM devascularization was achieved in 12 (37.5%) patients. Moreover, 76% to 99% AVM was achieved in 18 patients (56.3%), and 50% to 75% in 2 patients (6.3%). Bleeding, pain, heart failure, and cosmetic deformities were the indications for treatment. For 3 patients (3/32, 9.4%) who had bleeding, the treatment stopped the hemorrhage. Complete pain relief was reported in 8 patients (8/32, 25.0%), whereas complete relief from congestive heart failure post-embolization was observed in 5 of the 6 patients with congestive heart failure (5/6, 83.3%). Complete correction of cosmesis deformities after embolization was achieved in 10 patients (10/32, 31.3%). Two patients who underwent surgery to correct persistent deformity after embolization only showed insignificant improvement. In addition, 6 (18.8%) patients developed 13 complications including blister, necrosis, hemothorax, transient hemoglobinuria, and transient pulmonary artery hypertension.Conclusions: Ethanol embolotherapy is a safe and effective procedure for chest well AVMs. Surgery is required for some patients with residual cosmesis deformity.Clinical Impact Currently, there is no standard treatment for chest well AVMs due to their rarity and high heterogeneity. The present study shows that thanol embolotherapy is a safe and clinically effective treatment procedure for the chest well AVMs. Transarterial embolization in combination with direct puncture embolization can reach the AVM nidus. Ethanol embolotherapy can achieve complete obliteration of the AVM nidus in the majority of patients. Surgery may still be needed to correct cosmetic deformity after embolization. The present study provides valuable evidence to inform clinical decision-making.

The evolution of vascular plants during the Devonian Period has had great impacts on terrestrial ecosystems through innovations of key characters such as leaves, heterospory, seed reproduction, and woods. Here we report a new plant, Qianshouia miran. gen. n. sp., from the Upper Devonian Wutong (Wutung) Formation of Fanwan section, Changxing County, Zhejiang Province, China. This plant has slender axes which seldom branch. Its leaves are arranged in pseudowhorls, departing from axes with an acute angle. The leaves are strap-shaped and each can be subdivided into proximal, middle and distal portions. At the proximal portion, a middle ridge develops, and at the middle portion this ridge divides at least three times forming four to six daughter ridges, and in between are grooves. The distal portion of leaves (leaf apex) is suggested to be adaxially curved, with no ridges but with forked tips. Qianshouiaprobably represents a small plant with a shrubby or herbaceous habit. Due to the unique leaf morphology and the lack of fertile structures and anatomy, the exact phylogenetic position of Qianshouiais uncertain. Qianshouiamight be a lycopsid in light of the pseudowhorled phyllotaxis, or alternatively, could be a sphenopsid if the dichotomous ridge system of the leaf could be demonstrated to be leaf veins. Nevertheless, Qianshouiaadds to the diversity of leaf morphologies among the Late Devonian vascular plants.

MonilistrobusWang et Berry is a fossil lycopsid reported from the Upper Devonian Wutong Formation of Jiangsu Province, China, and includes only the type species Monilistrobus yixingensisWang et Berry. Along a single fertile axis, Monilistrobushas cone-like structures separated by and alternated with a length of vegetative region, which is an important character here termed as periodicity of reproductive growth. The alternation of fertile and vegetative growth occurs regularly and produces repeated intercalary (non-terminal) fertile zones. New specimens, identified as Monilistrobuscf. yixingensis, from the same formation but of Zhejiang Province extend the geographic distribution of this genus. These new specimens demonstrate morphological variations within this genus, such as the lack of spiny appendages on the leaves, different measurements of leaf bases, and different shapes and positions of cone-like structures. The distribution of intercalary fertile zones, as summarized for the first time in this paper, occurs in the Drepanophycales, the Protolepidodendrales, the Isoëtales, the Lycopodiales, the Selaginellales, and WuxiaBerry, Wang et Cai and Monilistrobusof uncertain affinities. Thus, this peculiar trait might have evolved in the very early evolutionary stage of the lycopsids, as indicated in the basal group Drepanophycales. However, the presence of repeated, two or more intercalary fertile zones along a single fertile axis is demonstrated only in Monilistrobusand the extant HuperziaBernhardi.

This paper presents the design of Unmanned Aerial Vehicles (UAVs) formation flight control laws and then the virtual Environment setup of a nice structure for close formation flight. The images of the target airplane projected on the video-camera plane of the follower airplane are captured and processed into vision information The simulation setup includes airplane dynamics, autopilots and formation keeping controller and module that creates virtual environment for the simulation of the vision software called Unity3D. The UKF is applied to the relative motion estimator due to the highly nonlinear characteristics of the problem.

The earliest ovules in the Late Devonian (Famennian) are surrounded by a cupule that is involved in both protection and pollination, and generally have free integumentary lobes. Here we report a new taxon from the Famennian of China, Guazia dongzhiensisgen. et sp. nov. The terminally borne ovule is apparently acupulate (without cupule) and has four radially arranged wing-like integumentary lobes that are extensively fused, and folded lengthwise and inwards. Guaziaprovides evidence that not all Devonian seeds possess a cupule and it increases their diversity in integumentary lobes. This genus also suggests that the integuments develop new functions, probably including wind dispersal at the expense of the cupules.The Late Devonian ovule or seed reported in this paper lacks cupule, which was believed to characterize the earliest seed plants in the Famennian. Instead, the unique integument functions as protection, pollination and probable wind dispersal.

The aim is to study the major afforested plants in heavy metal pollution area, so as to study the mechanism of heavy metals absorption of plants. Through surveyed dominant tree and analyzed heavy metal content in different parts of its body, and analysed heavy metal content in different species of main shrubs and herbs. The results show that: (1)The dominant tree is Koelreuteria paniculata which can adapt to different heavy metals pollution. Through its own physiological regulation such as stores preferentially in the vacuole of leaf epidermal cells, accumulates in apoplast of the adaxial epidermal cell wall and combines organic acid or a variety of peptides to form chelates in leaves, so as to degrade heavy metal. Main heavy metal (Mn) content in its body show that: leaves> bark> roots> branches> stems. (2) shrubs and herbs have different heavy metals absorption capacity, which show that: Canna warscewiezii>Thalia dealbata>Boehmeria>Pontederia cordata>Typha orientalis>Softstem bulrush>Iris germanica>Nerium oleander>Phragmites australis.

Water-rich and soft fault fracture zone is the geologic disaster source of water and mud outbursts in tunnel while the curtain grouting is an effective management method. To determine appropriate parameters of the grouting reinforced circle, depending on fluid-solid coupling theory and numerical simulation of the seepage fieldstress field, the influence of parameters to the water inflow and stability is analyzed while grouting effect was evaluated from the two aspects of reinforcement and water plugging. The conclusion show: the permeabilitystrength and thickness of the grouting reinforced circle are important factors of water inflow and surrounding stability while the choice of the thickness is inflected by the permeability and strength, when which reached a certain value the minimum thickness of the grouting reinforced circle is gotten.

Demonstration project attempted to restore the terrestrial habitats around wetlands and reduce the manganese (Mn) pollution of wetlands. Project had tested five kinds of trees for phytoremediation in terrestrial habitats, and designed Ecological interception system (EIS) to control the Mn pollution to wetlands. EIS was composed of the surface runoff collection system (SRCS) and the Treatment system (TS). SRCS composed of cobblestones, high-capacity adsorbent fillers, sands and plants. TS composed of three subsurface wetland units processing modules. The results show that: (1)New soil and base fertilizer applied in the plant pits can effectively improve plants survival rate; (2)Koelreuteria paniculata, Elaeocarpus sylvestris and Paulownia can be used for phytoremediation in terrestrial habitats; (3)Canna warszewiczii, Boehmeria, Thalia dealbata and other nine kinds plants in the EIS can absorb the Mn element effectively; (4)EIS can purify the water effectively. The complex project was based on the biological principles, ecological principles and biochemical effects which provides a reasonable ecological engineering model suitable for the restoration of polluted wetlands.

Euler-Euler two-fluid model was used to construct control equations of gas-solid two-phase flow, based on SIMPLE algorithm of collocated grid and FLUENT software, the pressure distribution of air-flowing field and dust field diffusion in fully-mechanized excavation face with different air-draft volume were simulated. The results show that with the increase of exhausted dust ability, diffusion intensity of producing dust pollution in driving head constantly decreases. Compared to air-draft volume of 320m3/min, when it is 600m3/min, the average dust concentration at the driver and whole section positions respectively decrease 51.28% and 56.51%, and high-concentration dust diffusion distance of the other workers position section decrease from 13.6m to 8.5m. Engineering Application indicates that the measured dust concentration is basically anastomosed with simulation result. When air-draft volume of dedusting fan is 600m3/min and dust control system with air curtain formed by forced fan drum is used, the dedusting rates of total coal dust and respirable dust on spot are respectively 95.1% and 96.1%, which achieves a great dedusting effect.

A high performance full adder circuit with full voltage-swing based on a novel 7-transistor xor-xnor cell is proposed in this paper. In our design, we exploit a novel 7-transistor xor-xnor circuit with a signal level restorer in a feedback path to settle the threshold voltage loss problem. Then we present a new high-performance 1-bit full adder based on the designed xor-xnor cell, pass-transistors and transmission gates. The simulation results prove that, compared with other designs in literature, the proposed full adder shows its superiority for less power dissipation, lower critical path delay and smaller power-delay product, and still provides full voltage swing in all nodes of the circuit.

RFID has been widely used in high security applications due to its contactless characteristic and security mechanism, such as e-ticket, e-money, e-key and so on. Since magnetic stripe card and traditional Mifare RFID card can be broken, it is a general trend to change them with CPU card. Based on the above fact, an entrance access control system is proposed in this paper using ISO/IEC 14443-A standard to replace some unsecure card. The following measures were introduced: 1, to design a kind of RFID reader which can be easily installed on the entrance; 2, to introduce PSAM card and its security function; 3, to design a security authentication mechanism using random number and 3DES encryption algorithm. With this system, the access control becomes more security and manageable, the proposed system is cost efficient and is successfully used in some companies.

Based on specimens from the Middle Devonian (Givetian) of Zhanyi County, Yunnan Province, China, we reinvestigate the morphology and anatomy of the protolepidodendralean lycopsid Minarodendron cathaysiense (Schweitzer & Cai) Li. New features of this plant include the stem up to 60 mm wide, axes dichotomizing as many as seven times, and microphylls with entire margins. Present anatomical characters conform to those known previously. The proportion of cortex area to stem (axis) area in cross section is proposed as an index to characterize the growth habit of the protolepidodendralean and isoëtalean lycopsids of the Middle Devonian to Carboniferous age. The thick stem and axes as well as high cortex proportion suggest that M. cathaysiense was probably a small tree. The Protolepidodendrales may have developed an arborescent habit in the late Middle Devonian.

Adiabatic self-heating tests had been conducted on Dafosi coal. Analysis of the relationship of temperature and reaction rate revealed that the dependence of coal sample temperature on reaction rate can be described by a third order polynomial from 40℃ up to 155℃. But at a small interval of temperature, the reaction rate still conforms to the Arrhenius kinetic model. When Arrhenius equation is used to solve the kinetic parameters of the coal spontaneous combustion, the coal temperature should be processed in segment.

C80 micro calorimeter was applied to investigate the initial heat release temperature and heat output at low-temperature oxidation process of Kabuliang anthracite coal under the experimental conditions of different coal sample mass, different temperature rising rates and different gas flow, and analyzed the effect of experimental conditions on test results. The results indicate that the coal sample mass and temperature rising rate affect measurement results, while there is no effect of gas flow. Under the same experimental condition, a higher temperature rising rate leads to a higher initial heat release temperature and less output of heat; The initial heat release temperature shows the trend of increase after decrease with the increase of coal sample mass. So, when micro calorimeter is used to investigate the coal low-temperature oxidation process, the experiments under the conditions of appropriate coal sample mass and the lower temperature rising rate can obtain more accurate test parameters.

Water-bearing fault of subsea tunnel has fissure water developed, fractured surrounding rock with low strength, which gets a risk of sudden water inflow and affects the tunnel security. This paper takes the geological forecast and treatment for water-bearing fault of the Qingdao kiaochow bay subsea tunnel for example, according to the water assignment characteristics, using the detect method of TEM and advance borehole to make accurate decision for the position of water-bearing body、the scale of fracture zone and the inflow of water. Through the analysis of results, the grouting form, materials and parameters are chosen and adjusted. The grouting material seals the water flowing fracture, forming water-stopping curtain outside tunnel excavation contour line and strengthening the fault fracture zone to improve the stability of rock.

Breviflavone B is a novel chiral phytoestrogen that mimics the biological functions of 17β-estradiol (E2), an estrogen which is naturally produced in our body. It has exhibited a much higher estrogen receptor (ER) bioactivity than E2 or other phytoestrogens. Breviflavone B specifically activates ER at a low dose without activating other steroid receptors, and inhibits estrogen-stimulated breast cancer cell proliferation at high doses, making it a potential treatment option for breast cancer patients. In this report, a new liquid chromatography aprroach has been developed to isolate Breviflavone B from Epimedium Brevicornum herbal extracts. After passing through DIAION HP20 resin, the ethanolic extract of Epimedium Brevicornum was firstly fractionalized by a Diol column, then further separated by a C18 column using preparative HPLC, and finally purified by an ODS-MCR-HPS column in HPLC under gradient mode. In each stage of separation, the ER bioactivities of the each fraction were measured by estrogen receptor-driven reporter gene bioassays to guide the chromatographic fractionations. The results showed that the new combination of Diol and C18 and ODS-MCR-HPS column chromatography provided better separation selectivity than our previously-reported C18 column chromatography for isolation of Breviflavon B from Epemidium herbs. Pure Breviflavon B was successfully isolated from the ethanolic extract of Epimedium Brevicornum herb via this new approach of chromatographic fractionations guided by the bioassays.

Low temperature oxidation of two different low rank coals was measured by in-situ FTIR. Curve-fitting analysis was employed to identify functional groups types of raw coals, and series technology was carried out on in-situ infrared spectrum of sample coals at low-temperature oxidation process to analyze the changes of main active functional groups with temperature. The results indicate that -CH3, -CH2, -OH, C=O, COOH are the main active functional groups in low rank coal. In the oxidation process, with temperature increasing, the methyl and methylene show the tendency of increase after decrease and then decrease, and all of hydroxyl, carboxyl and carbonyl group present the tendency of increase after decrease, there exists some differences among the main functional groups in the coal low-temperature process.

Vortex air curtain of plane wall fan drum can control the diffusion of air stripping dust effectively. In order to solve the high-concentration dust problem in fully mechanized excavation face, formation mechanism of vortex air curtain was analyzed. According to fluid mechanical control equations of gas phase flow, mathematical model was established to solve air migration law of vortex air curtain in fully mechanized excavation face. By using Simple algorithm based on collocated grid and fluent software, numerical simulation of air spatial migration law of closed-end dust control in fully mechanized excavation face was carried out. The simulation results show that vortex air curtain dust control system can form dust control fan drum along driving head to the front of the roadheader driver. According to the simulation results and actual conditions of working face field, vortex air curtain suction dust control system consisted of plane wall fan drum and exhausted dust purification device in fully mechanized excavation face was designed, and after it was applied in fully mechanized excavation face, the dust concentration decreased effectively in the working face field.

The numerical simulation of migration rule about dust flow field in typical long forcing and short exhausting mixed ventilation dust removal system of half-coal rock fully-mechanized excavation face was carried out, and local ventilation system was improved based on the simulation results. The relative position relationship of ventilation facilities and the matching relationship of forcing and exhausting air volume in half-coal roadway were made sure, thus, the new complete sets of ventilation wet dedusting system with the type of KTCS-500L had been developed. According to the application in Nantun coal mine of Yanzhou mining group, the system proved to be very effective.

The whole rock fully-mechanized excavation with big cross section, high rock hardness and strong cutting intensity of fully-mechanized coal winning machine has a higher dust concentration than coal roadway excavation, so ventilation dust removal technology is in need in whole rock face. Based on the dust migration and distribution numerical simulation in whole rock tunnel excavation, optimization design of long pressing and short pumping hybrid ventilation and dust removal system were carried out. Eventually, the comprehensive dust prevention measures with air curtain closing dust source, dust electromotor exhausting dust and retaining curtain capturing dust were realized in this paper, which achieved a good removal efficiency of dust.

Foam is a high efficient technology for controlling dust in underground coal mine,and foam generator is one of the core components of the technology. Aiming at designing the key structural parameters of foam generator scientifically, the velocity and pressure distribution of foam generator under different parameters were simulated and displayed by CFD (Computational Fluid Dynamics) software. The results show that the intensity of gas-liquid mixture in foam generator reaches the maximum when the vortex generator is 24mm away from the throat and the baffle with a 45° angle. Under the circumstances, the pressure is well-distributed around the vortex generator and the outlet of foam generator, and the foaming effect best.

An advanced numerical model and its application in thermal processing of nonlinearly anisotropic scattering semitransparent materials are presented in this paper. The decomposition of the radiative transfer equation is deduced using spherical harmonics (PN-approximation) method. Considering the transient problem, coupled radiative and conductive heat transfer model based on arbitrary-order PN-approximation method is established. With the coupled model, the calculation accuracy of high-order PN-approximation method is verified through comparison with theoretical solution and by the simulation results of other methods. Comparison shows that the arbitrary-order PN-approximation method reproduces results with a high accuracy for linear and non-linear anisotropic scattering, while it can easily treat the nonlinear anisotropic scattering phase functions with desired order. Keywords: semitransparent material, coupled heat transfer, numerical simulation, spherical harmonics method

In different conditions (time, temperature and coal particle size), oxygen physisorption of different coal samples were tested by a oxygen adsorption detection instrument with chromatograph, followed by the analysis of the relation between oxygen physisorption in coal self-heating and the propensity of coal to spontaneous combustion. The results indicate that the physisorption reaches 80% of the saturate amount in several seconds, and then with the rapid decline of the sorption rate takes about 1 min to get saturated. The physisorption decreases with the temperature rise, and increases then drops with decreasing coal particle size, only playing a role in oxygen transportation, physisorption heat generation and the first motivation for coal to self-ignite. The content of oxygen physisorption cannot reflect the capacity of chemisorption and chemical reaction during spontaneous combustion. It is concluded that the sole oxygen physisorption cannot identify the oxidation reactivity of coal effectively.

Coal fires are emerging as a global threat with significant economic, social and ecological impacts, besides the loss of energy resources those fires cause air and water pollution and emit enormous amounts of green house gases (carbon dioxide and methane), how to prevent and extinct the fires has been a worldwide issue. According to the respective limitation and characteristic of gel fire prevention materials and foam fire prevention materials, a new thinking of foamed gel coal fire prevention materials is put forward creatively. Foamed gel that includes the characteristic of gel and foam possessed the property of accumulation. It also has the performance of sealing and secluding oxygen. This paper describes the composition and characteristic of foamed gel, as well as the laboratory production process. For large coal fire zones, the new fire prevention materials (Foamed Gel) have a broad application prospect.

In order to overcvome the shortage of current dust control technology in coal mine, especially the traditional water spray method, a two-phase foam materials preparation experimental system was established based on the simulation of water and air conditions in underground coal mine. And a new technique which can prepare high-performance foam was proposed, and the main technical parameters and application conditions to implement foam dedusting were determined through plenty of experimental. Then, the new technique had been applied in two large underground coal mine. The results show that its dedusting efficiency to total dust and respirable dust reached 90.5% and 85.4% in the fully-mechanized excavated face, as 1.97 times and 1.88 times higher than water spray respectively. However, its water consumption is only as 10% to 20% as conventional water spray. It is proved that this new technique for preparation of foam can reduce mine dust concentration remarkably and improved the working environment obviously, and has a broad application prospect and promotion value to control dust in underground coal mines and other related industry.

Study on multivariate calibration for infrared spectrum of coal was presented. The discrete wavelet transformation as pre-processing tool was carried out to decompose the infrared spectrum and compress the data set. The compressed data regression model was applied to simultaneous multi-component determination for coal contents. Compression performance with several wavelet functions at different resolution scales was studied, and prediction ability of the compressed regression model was investigated. Numerical experiment results show that the wavelet transform performs an effective compression preprocessing technique in multivariate calibration and enhances the ability in characteristic extraction of coal infrared spectrum. Using the compressed data regression model, the reconstructing results are almost identical compared to the original spectrum, and the original size of the data set has been reduced to about 5% while the computational time needed decreases significantly.