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In this paper, a high-speed successive approximation analog-to-digital converter is designed based on a 40 nm CMOS process. A split-capacitor Vcm-Based switching strategy is designed, which is able to keep the output common-mode voltage constant for the DAC capacitor array without using Vcm level drive, while saving half of the capacitance compared to the conventional switching strategy and greatly reducing the area consumption. It also combines the features of binary redundancy technology and non-binary redundancy technology by splitting the highest bit capacitor to the lower bit, which enables the DAC array to generate two additional redundant bits without adding other capacitors, reducing its requirements for noise and establishment accuracy; and it adopts asynchronous timing control without external clocks, which is conducive to improving the speed of SAR ADCs and reducing the design complexity. The designed SAR ADC achieves 9.83 bit effective bits, 60.9 dB signal-to-noise distortion ratio, 77.2 dB spurious-free dynamic range, 1.68 mW overall power consumption, and 18.46 fJ/conv-step superiority at a supply voltage of 1.1 V and a sampling frequency of 100 MHz through simulation.

A low-dropout linear regulator (LDO) with wide input voltage range, wide output voltage range and low quiescent current power consumption is proposed, which is applied to the switching power supply chip to power the internal module of the switching power supply chip. The low-dropout linear regulator is based on a P-type PowerFET design consisting of an error amplifier, a Bandgap reference. The circuit was designed and implemented by SMIC 0.18um BCD process, simulated and verified using Spectre software. The simulation results show that the linear regulation is 0.04mV/V in the input voltage range of 3.5-30V, and the load regulation is 1mV/mA in the output load current range of 10uA to 10mA, and the quiescent current is only 10uA.

This paper introduces a high-precision RC oscillator circuit that is less affected by temperature and supply voltage. The circuit mainly consists of a bandgap reference voltage source, a low-voltage linear regulator, a low-pass filter, and a digital trim circuit, which reduces the circuit's sensitivity to temperature variations and achieves high stability of the oscillator frequency over a wide temperature range. Because of the current digital trimming technique, the circuit's ability to cope with the effects of frequency instability caused by process deviations is further enhanced.The simulation results show that the output center frequency accuracy is maintained within ±0.5% under the supply voltage range of 2.5V~5.5V, temperature range of -40?~125?, and different process corners. The RC oscillator has a high precision output frequency and can be used as a clock signal for a number of highly integrated and high precision applications.

KVM denotes the initials of the keyboard, monitor and mouse of a computer. digital KVM systems are composed of two parts, one is the device terminal and the other is the software adapted to this device terminal. KVM systems are emerging remote centralized management technologies for multiple devices in multiple locations based on IP networks in recent years [1,2]. digital KVM systems mainly use IP networks to control remote computers to control remote computers mainly through IP networks [3]. Therefore, KVM systems are widely used in computer management and remote control of computers. In practical applications, the compression efficiency of images is relatively low and the delay of mouse movements is relatively large. To address these two shortcomings, this paper designs a software based on the RK3399 processor, which on the one hand performs fast image acquisition and high-quality encoding, and on the other hand realizes input control of the target computer through the mouse and keyboard control chip UI012.

Mg(OH)2 whiskers were successfully prepared under mechanical stirring with D301 ion exchange resin and Mg(NO3)2. The products were systematically characterized by testing settling ratio, turbidity, and analyzing SEM, FT-IR. The results showed that Mg(OH)2 prepared with 0.05 or 0.1 mol/L Mg(NO3)2 had excellent dispersion, and the settling ratio was close to 100 % after 360 min; The time extension was extremely helpful to improve the dispersion; The dispersion of product was correspondingly good under pH value of about 9. The products synthesized with different concentrations and reaction time could reach nanoscale, and the product obtained using 0.05 mol/L Mg(NO3)2 for 4 h had whisker structure with a length of 10 im and had a lipophilicity. FT-IR analysis showed the product included some functional groups or fragments from the resin, which had a positive modification effect on the products. The preparation of Mg(OH)2 whisker with resin as raw material is simple, green, and environmentally friendly, which is worthy of further application.

Thyroid carcinoma (THCA) is the most prevalent tumor in the endocrine system with an increasing incidence. Recent studies have underscored the function of microRNAs (miRNAs) in THCA. Nevertheless, knowledge regarding the effects of exosomal miRNAs in THCA is still limited. This report intended to probe the regulatory effects of exosomal miR-152 on THCA and the underlying mechanism. The expression profile of miR-152 was studied in clinical samples as well as B-CPAP and TPC-1 cells. Transwell, CCK-8, and flow cytometric assays were performed to investigate the roles of miR-152 on invasion, migration, proliferation, and apoptosis in B-CPAP and TPC-1 cells. The putative target of miR-152 was predicted using the bioinformatic analysis, and the targeting relationship was confirmed verified subsequently. Afterward, exosomes were isolated from bone marrow mesenchymal stem cells (BM-MSCs) and co-cultured with B-CPAP and TPC-1 cells to explore the function of exosomal miR-152 on THCA cells. miR-152 was reduced in THCA tissues and cells. Restoration of miR-152 inhibited proliferation, invasion and migration of B-CPAP and TPC-1 cells, but promoted cell apoptosis. Dipeptidyl dipeptidase 4 (DPP4), a target of miR-152, was found to promote THCA cell invasion and migration. miR-152 ferried by BM-MSCs-derived exosomes repressed THCA cell invasion and migration, and pcDNA-DPP4 weakened the repression effect. Exosomal miR-152 inhibited proliferation, migration and invasion of THCA cells by binding with DPP4, which may represent a novel target for the treatment of THCA.

Hydrothermal carbonization (HTC) combined with anaerobic digestion (AD) is a cost-effective process to simultaneously treat biomass wastes for hydrochar production, energy recovery, and wastewater ...

Suitable anode materials with high capacity and long cycling stability, especially capability at high current densities, are urgently needed to advance the development of potassium ion batteries (PIBs) and sodium ion batteries (SIBs). Herein, a porous Ni-doped FeSe

Developing a conductive catalyst with high catalytic activity is considered to be an effective strategy for improving cathode kinetics of lithium-sulfur batteries, especially at large current density and with lean electrolytes. Lattice-strain engineering has been a strategy to tune the local structure of catalysts and to help understand the structure-activity relationship between strain and catalyst performance. Here, Co

A novel NiCo2O4/N-doped carbon nanowebs serving as a bifunctional electrocatalyst, consisting of hollow NiCo2O4 nanospheres and N-doped carbon nanowebs are prepared through a liquid-phase synthesis method accompanied by subsequent heat treatment. The N-doped carbon nanowebs mainly contribute to the high activity for oxygen reduction reaction, whereas the NiCo2O4 nanospheres act as an active phase for oxygen evolution reaction. The electrocatalytic performance is promoted by the synergistic effect between NiCo2O4 and N-doped carbon nanowebs. Benefiting from the hollow and N-doped structure with merits of more activity sites, fast charge and mass transport, the NiCo2O4/N-doped carbon nanowebs exhibit an excellent bifunctional catalytic activity, high selectivity of the apparent 4e− pathway, small ΔE values and long-term durability. Rechargeable Zn-air batteries using NiCo2O4/N-doped carbon nanowebs as catalyst display a lower overpotential, a high capacity (826.9 mAh g−1), a high energy density (954.2 Wh Kg−1) and long-term stability (600 cycles at 5 mA cm−2), when compared to commercial Pt/C + Ir/C. Furthermore, the NiCo2O4/N-doped carbon nanowebs is directly used as air catalyst in flexible Zn-air batteries, which also exhibit superior flexibility and cycling stability. This work provide a new method for developing highly efficiency electrocatalyst, rechargeable and flexible Zn-air batteries.

This paper proposes a self-learning enhanced energy management for plug-in hybrid electric bus (PHEB). Two innovations are made to distinguish our contributions from others. First, a target preview-based reference SOC plan method is proposed, where a linear reference SOC trajectory will be re-planed at fixed time steps (every 60 s) by taking the expected SOC at the destination as the target, and a feasible zone is exclusively defined to provide a margin for the fuel economy improvement. Second, a reinforcement learning-Pontryagin's minimum principle (RL-PMP)-based energy management constituted by the RL and PMP algorithms is proposed, where the average velocity with time moving, the SOC, and the normalized trip distance are taken as states and the co-state is taken as the action. Different from the conventional RL methods, the co-sate is only updated at the fixed time step, and the reward will be evaluated in the next 60 s. This can greatly accelerate the training process of the RL-PMP. In addition, the driving conditions in the next 60 s are predicted by a designed Markov chain. The simulation results demonstrate that the fuel economy of the RL-PMP is close to the dynamic programming (DP) and can be averagely improved by 14.155% compared to the rule-based control strategy.

Background. Hepatoma is a leading cause of death worldwide, with high metastasis and recurrence rates. The aberrant expression of miRNA-130a-5p is involved in the development and progression of various cancers. However, there are no studies investigating the role of miRNA-130a-5p in hepatoma. The present study is aimed at clarifying the functional role of miRNA-130a-5p in hepatoma progression. Methods. The expression levels of miRNA-130a-5p in hepatoma tissues and cell lines were detected by qRT-PCR assays. Bioinformatic analysis, gain-/loss-of-function experiments, and luciferase activity assays were conducted to verify whether miRNA-130a-5p is targeted by protein tyrosine phosphatase 4A2 (PTP4A2). The functions of miRNA-130a-5p and PTP4A2 in hepatoma were determined by cell proliferation assays. Results. The expression of miRNA-130a-5p was downregulated in hepatoma tissues and was related to poor prognosis. However, the expression level of PTP4A2 was contradictory to that of miRNA-130a-5p, and PTP4A2 upregulation could aggravate hepatoma progression. The ectopic overexpression of PTP4A2 promoted hepatoma cell proliferation in vitro, which could be reversed by miRNA-130a-5p. Conclusions. Our study implies that miRNA-130a-5p, which is downregulated in hepatoma tissues, can suppress hepatoma cell proliferation via targeting PTP4A2.

The microalgae and macroalgae-based hydrochars produced by hydrothermal carbonization were mainly used as biofuels, however, their application in anaerobic digestion (AD) was little known. This study investigated the effects of microalgae Chlorella-based hydrochar (HC-C) and macroalgae Laminaria-based hydrochar (HC-L) on a continuous AD reactor under different organic loading rates (OLR). The AD process stability of hydrochars supplemented reactors were performed well under the increase of OLR from 2.6 to 6.5 g COD/L/d, and HC-C and HC-L addition could significantly enhance the daily methane yield by 36.0% and 31.4%, respectively. Interestingly, the possible mechanisms of HC-C and HC-L on the enhanced AD were similar, namely increasing sludge granulation, promoting the Methanothrix relative abundance and key enzyme activities, and further facilitating potential direct interspecies electron transfer between methanogens and organic-degrading bacteria. This study provided an implication on the potential application of algae-based hydrochars in wastewater treatment and energy recovery.

Dysarthria is universal in Parkinson’s disease (PD) during disease progression; however, the quality of vocalization changes is often ignored. Furthermore, the role of changes in the acoustic parameters of phonation in PD patients remains unclear. We recruited 35 PD patients and 26 healthy controls to perform single, double, and multiple syllable tests. A logistic regression was performed to differentiate between protective and risk factors among the acoustic parameters. The results indicated that the mean f0, max f0, min f0, jitter, duration of speech and median intensity of speaking for the PD patients were significantly different from those of the healthy controls. These results reveal some promising indicators of dysarthric symptoms consisting of acoustic parameters, and they strengthen our understanding about the significance of changes in phonation by PD patients, which may accelerate the discovery of novel PD biomarkers.

Naphthenic acids (NAs) are a persistent toxic organic pollutant that occur in different environment worldwide and cause serious threat to the ecosystem and public health. However, knowledge on the behavior and fate of NAs in marine environments still remains unknown. In this study, the degradation mechanism of NAs (cyclohexylacetic acid, CHAA) was investigated using an common indigenous marine Pseudoalteromonas sp. The results showed that CHAA could be degraded completely under aerobic condition, but could not be utilized directly under anaerobic condition. Interestingly, transcriptome and key enzyme activity results showed the CHAA degradation pathway induced under aerobic condition could still work in anaerobic condition. The degradation was activated by acetyl-CoA transferase and sequentially formed the corresponding cyclohexene, alcohol, and ketone with the assistance of related enzymes, and finally cleaved by hydroxymethylglutarate-CoA lyase. Besides, there was a positive correlation between chemotaxis and aerobic degradation genes (r = 0.976, P 0.05), the chemotaxis would enhance bacterium movement and NAs biodegradation. It is proposed that bacterium could translocate to NAs and accomplish biodegradation from aerobic to anaerobic environments, which was a new anaerobic degradation pathway of NAs. This study provides new insights into the fate of NAs and other organic contaminants in marine environment.

Domoic acid (DA) is a major marine neurotoxin, occurs frequently in most of the world's coastlines and seriously threatens ecosystem and public health. However, information on its biotransformation process in coastal anaerobic environments remains unclear. In this study, the underlying mechanism of anaerobic biotransformation of DA by marine consortium GLY was investigated using the combination of liquid chromatography-high-resolution Orbitrap mass spectrometry and comparative metatranscriptomics analysis. The results demonstrated that DA could be cometabolically biotransformed under anaerobic conditions with pseudo-first-order reaction. Anaerobic biotransformation pathway of DA was clarified, including decarboxylation, dehydrogenation, carboxylation activation with CoA and multiple β-oxidation steps occurring at aliphatic side chain, which facilitated DA detoxification. Furthermore, anaerobic cometabolic biotransformation mechanism of glycine-DA by consortium GLY was established for the first time, a number of genes related to the metabolic pathways of glycine fermentation, fatty acid synthesis and β-oxidation were responded in the consortium GLY transcriptome and involved in the anaerobic biotransformation of DA. This study could deepen understanding of interaction mechanism between toxin DA and marine microorganisms, which provides a new insight into the DA fate and its effects on benthic microbial community in marine environments.

KNiFe(CN)6/C/NF catalyst is prepared by a simple hydrothermal reaction. In this catalyst, the cubic structure of KNiFe(CN)6 grows on the surface of the nickel foam (NF) to form a three-dimensional network structure. The formation of KNiFe(CN)6 is based on the substitution of K+ by Ni2+ in K3[Fe(CN)6]. During this substitution process, some K+ vacancies will be formed in KNiFe(CN)6, so that the catalytic activity can be improved. The KNiFe(CN)6/C/NF catalyst shows exhibited efficient electrocatalytic activity for oxygen evolution reaction, requiring low overpotentials of 69 and 231 mV to achieve 10 and 100 mA cm−2 current densities in 1.0 M KOH solution. When it is used as a catalyst for ZABs, KNiFe(CN)6/C/NF shows excellent high stability within 1000 cycles with a charge-discharge overpotential gap of 0.85 V at 5 mA cm−2. The flexible battery assembled based on the KNiFe(CN)6/C/NF catalyst also has excellent performance, which can maintain stable charge and discharge within 50 cycles at a current density of 5 mA cm−2.

This work used nickel foam (NF) as a conductive substrate to construct a self-supporting structure catalyst, which exhibited excellent bifunctional catalytic activity for both oxygen evolution reactions (OER) and hydrogen evolution reactions (HER). Through CoMo-MOF and NF sulfuration together, NF surface participates in the reaction and grows uniform needle-shaped Ni3S2 nanorods, while CoMo-MOF transforms into CoMoSx hollow polyhedral particles, which are attached to the surface of Ni3S2 rods and formed Ni3S2-CoMoSx/NF composite. It was found that there is an obvious synergistic effect between CoMoSx, Ni3S2 and NF, thus obtaining excellent catalytic activity for both OER and HER. The overpotential of Ni3S2-CoMoSx/NF catalyst at 10 mA cm−2 is only 234 and 90 mV for HER and OER. In addition, Ni3S2-CoMoSx/NF also exhibits excellent performance in the process of overall water splitting. It can reach 10 mA cm−2 at only 1.52 V and the catalytic performance remain stable for 65 h. Therefore, the self-supporting Ni3S2-CoMoSx/NF can become a highly efficient and long-term durable bifunctional electrocatalyst for overall water splitting.

Polyacrylate containing wastewater (PCW) is the typical sewage discharged by the textile industry. It has extremely poor biodegradability, and chemical methods were used conventionally as the only way for treating PCW. This study is demonstrating a novel biological method. In batch experiment monod kinetics was applied to the experimental data, which indicated that anaerobic treatment used for PCW is feasible. The pilot-scale experiment combined a Spiral Symmetry Stream Anaerobic Bioreactor (SSSAB) and an air-lift external circulation vortex enhancement nitrogen removal fluidized bed bioreactor (AFB). The COD and NH4+-N removal reached up to 95.2% and 96.6%, respectively, which were higher than the value obtained by other chemical methods. High-throughput sequencing analysis indicated that the relative abundance of Proteobacteria, Firmicutes and Bacteroidetes increased, which contribute to the degradation of PCW. Therefore, PCW can be degraded efficiently by using a SSSAB-AFB technique and thus provides an alternative to the chemical methods.

The Dongfengshan gold deposit in Heilongjiang Province of China is located at the western margin of the Jiamusi Massif. The mineralization is closely related to the intrusion of the Permian granite porphyry. In this paper, we present new zircon U–Pb ages and whole-rock geochemical analyses of the granitoids from the Dongfengshan deposit. They are classified as peraluminous high-K calc-alkaline to shoshonitic A-type granites, with enrichment in the large ion lithophile elements (e.g., Rb, U, and Th) and depletion in the high field strength elements (e.g., Nb, P, Ti, and Zr) and clear negative Eu anomalies. The zircons from the granite porphyry are both magmatic and hydrothermal, with the former yielding ages of 281.7 ± 3.3 and 282.1 ± 3.5 Ma that represent the timing of crystallization of this Early Permian pluton. The hydrothermal zircons yield an age of 280.5 ± 0.3 Ma, representing the hydrothermal age, which coincide with the emplacement of the igneous rocks. These data suggest that the Early Permian magmatic and mineralization event led to the formation of the Dongfengshan gold deposit. In comparison, zircons from the monzogranite yield a weighted age of 523.0 ± 6.4 Ma, indicating that magmatism of the study area occurred in the Early Cambrian. On the basis of the regional geological history and the new geochemical and isotopic data from intrusions, we suggest that diagenesis and mineralization of the Dongfengshan gold deposit took place in a postcollisional extensional tectonic setting during the Early Permian.

Conductive magnetite (Fe3O4) has been applied into some anaerobic bioprocesses to accelerate direct interspecies electron transfer (DIET), however, Fe3O4 is usually dissolved by iron-reducing bacteria under anaerobic conditions, resulting in the loss of magnetite. Therefore, submicron magnetite particles were added to the sequencing batch reactor (SBR) to build a Fe3O4/SBR system, which could alleviate magnetite dissolution and simultaneously remove tribromophenol (TBP) effectively. The average removal efficiencies of chemical oxygen demand (COD) and TBP in Fe3O4/SBR system were 81% and 91%, respectively, which were 51% and 18% higher than those of the control group without Fe3O4 (SBR system). The enhanced TBP biodegradation was likely related to potential DIET, which was supported by the scanning electron microscopy (SEM) analysis, the increase of dehydrogenase and heme c (fivefold and 1.7-fold), and the enrichment of iron-redoxing bacteria (Geobacter and Thiobacillus). Furthermore, magnetite mainly remained intact in structure as indicated by X-ray diffraction (XRD), which might be ascribed to in situ iron redox cycle and magnetite biosynthesis via Magnetospirillum. Notably, the content of hydrogen peroxide (H2O2) and hydroxyl radical (⋅OH) in Fe3O4/SBR system was 4–5 times higher than that of SBR system. These findings could provide insights into the development of cost-effective strategy for the removal of refractory organic pollutants.

In this work, hollow FeS2 nanospheres were successfully synthesized via a simple hydrolysis method followed by annealing and a sulfidation process. These nanospheres have diameters of approximately range from 300 to 400 nm and shells about 50 nm thick. Due to the unique hollow structures, these FeS2 reveal excellent long-cycling performance through improving the ratio of the pseudocapacitance effects in total charge storage. At a current density of 1 A g−1, the FeS2 anode delivered a high capacity of 541.5 mAh g−1 after 100 cycles. More importantly, these FeS2 could retain a capacity of 313.5 mAh g−1 after 500 cycles at a high current density of 5 A g−1, and still achieve a capacity of 147.2 mAh g−1 after 400 cycles at a higher current density of 10 A g−1.

In this work, we used Ni foam (NF) as a substrate to grow NiMn1.5PO4 thin layers on the surface of NF by a facile method. The NiMn1.5PO4 thin layer uniformly grows and covers on the surface of NF, thus form a three dimensional (3D) network structure. The 3D structure has a large specific surface area and a porous framework structure, which exhibited very low overpotentials and highly efficient hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The overpotentials of the NiMn1.5PO4/NF catalysts were 72 mV and 198 mV at 10 mA cm−2 for HER and OER process, respectively. When NiMn1.5PO4/NF was used as both anode and cathode electrocatalyst in 1 M KOH, a low cell voltage of 1.48 V was achieved at current density of 10 mA cm−2 and showed a good long-term stability for 50 h. In the process of overall water splitting, the H2 yield can be reached 4.17 μmol min−1.

Rational design of bifunctional oxygen catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with high efficiency and low-cost are significantly in the development of rechargeable Zn-air batteries (ZABs). Herein, it is designed one-dimensional rod-like Mn3O4/NiCo2S4 nanostructure. The inner Mn3O4 nanorod and the outer coating of the NiCo2S4 layers make the composite material have a stable structure, thus exhibiting a rather high bifunctional catalytic activity (ΔE = 0.74 V) and long-term durability toward ORR/OER. An interlaced region is formed at the interface of the dual phases by the Kirkendall effect, where Mn3O4/NiCo2S4 nanocrystals, oxygen vacancies and defects co-exist. The Mn3O4/NiCo2S4 exhibits an onset potential of 0.92 V and a half-wave potential of 0.81 V, and the OER potential is only 1.55 V at 10 mA cm−2. When using this catalyst in rechargeable ZABs, the batteries show a high power density (106.26 mW cm−2), superior rate stability, small charge-discharge voltage gap (0.86 V) and long-term cycles (650 cycles over 216 h at 5 mA cm−2). The flexible ZABs exhibit a high open-circuit voltage of 1.427 V and stably cycled 50 cycles (16.8 h) with a small charge-discharge voltage gap (0.5 V) at 1 mA cm−2.

Previous studies that have investigated marine oil pollution have predominantly focused on petroleum hydrocarbons. Naphthenic acids (NAs), in contrast, are toxins that are less well studied. Following the Dalian oil spill accident, monitoring surveys were carried out to investigate NAs in Dalian Bay sediments. Concentrations of NAs were between 14.826 and 34.279 mg kg−1, with acyclic and motorcycle carboxylic acids (43.28% and 35.12%, respectively) being the dominant components. NAs were 10–30 times more abundant than polycyclic aromatic hydrocarbons (PAHs) in the sediment. Further correlation analysis showed the abundance of NAs was highly correlated with total PAH levels (0.705, p

Artificial redox mediators (ARM) have been proven to accelerate the azo dye anaerobic bio-reduction (ADAB) but the mechanisms involved are still unclear. Previous studies do seldom focus on the production of methane during the ADAB, particularly if supplemented with ARM. Our studies revealed that the supplement of ARM could significantly accelerate the decolorization rate, recover the inhibited methanogenesis and decrease extracellular polymeric substance secretion in an ADAB system. Supplement of an ARM only enhanced the pre-existing metabolic pathway of the ADAB system. Significant differences in metabolic pathway and microbial community were found between traditional methanogenic system and ADAB system by high-throughput sequencing technique. The ADAB system performed an “over-requirement for electron donor” phenomenon and the requirement amount can be altered by regulating ARM dosage. Response surface methodology was then successfully employed to optimize the dosage of ARM and possible additional electron donor required for ADAB under different conditions.

Hydrothermal carbonization (HTC) is a promising thermo-chemical technology to treat wet biomasses for production of hydrochars but produces excessive process water. In this study, recirculation of process water from HTC of macroalgae Laminaria was investigated for 12 rounds. Recycling process water increased the hydrochar yield, carbon recovery rate and high heating value from 13.3% to 17.1%, from 22.9% to 32.6%, and from 18.4 MJ/kg to 20.5 MJ/kg after 12 rounds, respectively. The process water recirculation could partly alleviate the toxicity of process water through seed germination test. Volatile fatty acids (VFAs) predominantly accumulate with process water recirculation. The increased proportion of VFAs on chemical oxygen demand could promote methane production of diluted process waters, a 12.3% increase was observed in the round 10, compared with initial process water. These results showed that recycling the process water could reduce water consumption significantly and enhance energy recovery efficiency.

This study was conducted to examine effects of plant growth regulators and light resources on the formation of multiple shoot and plant regeneration of Hovenia dulcis var. koreana Nakai. Stem and shoot tip were cultured on MS medium or WPM supplemented with various plant growth regulators. At the single treatment, the highest shoot formation was obtained when stem explants were cultured on WPM supplemented with kinetin . MS medium containing NAA 0.1 and TDZ gave the best results for shoot induction rate and shoot growth in combination treatments. Of the BAP and kinetin tested, BAP on WPM was found to be more effective for shoot growth from shoot tip. Under white fluorescent light treatment, shoot growth was much higher than blue, red LED treatments. Root induction from in vitro growth of plantlet was the best on WPM supplemented with IBA. The results suggest that selection of plant growth regulators and light resources could be important factor to achieve an efficient in vitro growth.

This article focuses on the subject of iron ore. Though analyzing the relationship between iron ore consumption and economic development about China and American, it is found that the per capita consumption of iron ore in China was too early, which is not conducive to economic development. Through elaborating the relationship between the consumption and the industrial structure of iron ore, it is revealed that China's industrial structure changes with iron ore consumption intensity and China's economic growth is realized at an excessively high cost of resources.

Focused on the optimization of lunar ascent nominal trajectory, an algorithm based on the unscented Kalman filter (UKF) parameter estimation is proposed in this paper. The optimization of lunar ascent nominal trajectory problem requiring minimum fuel is formulated as a two-point boundary value problem (TPBVP) through the maximum principle. By treating the initial values of the costate variables as parameters to be estimated and setting the deviation of terminal values as target observations, the TPBVP is then transformed into a parameter estimation problem and solved by the UKF parameter estimation algorithm. Numerical simulation results demonstrate that the algorithm can be used to optimize lunar ascent nominal trajectory, it can also overcome the difficulty of guessing the initial values of the costate variables, and the calculating efficiency is higher than traditional optimization algorithm under the premise of guaranteed accuracy.