Thermogravimetric analysis and kinetic modeling of the co-pyrolysis of a bituminous coal and poplar wood

The co-pyrolysis of coal and biomass has proven to be a promising route to produce liquid and gaseous fuels as well as specific value-added chemicals while contributing to mitigating CO_(2) emissions.The interactions between the co-processed feedstocks,however,need to be elucidated to support the development of such a thermochemical conversion process.In this context,the present work covers the kinetic analysis of the co-pyrolysis of a bituminous coal with poplar wood.In this research,biomass was blended with coal at two different mass ratios(10%(mass)and 20%(mass)).Thermogravimetric analyses were carried out with pure and blended samples at four heating rates(5,10,15 and 30℃·min^(-1)).A direct comparison of experimental and theoretical results(based on a simple additivity rule)failed to yield a clear-cut conclusion regarding the existence of synergistic effects.Kinetic analyses have therefore been achieved using two model-free methods(the Ozawa-Flynn-Wall and Kissinger-Akahira-Sunose models)to estimate the rate constant parameters related to the pyrolysis process.A significant decrease of the activation energy has thus been observed when adding wood to coal(activation energies associated with the blend containing 20%(mass)of biomass being even lower than those estimated for pure wood at low conversion degrees).This trend was attributed to the possible presence of synergies whose related mechanisms are discussed.The rate constant parameters derived by means of the two tested models were finally used to simulate the evolution of the conversion degree of each sample as a function of the temperature,thus leading to a satisfying agreement between measured and simulated data.

A Spectroscopic Approach to Assess Heavy Metals Contents of the Mine Waste of Jalta and Bougrine in the North of Tunisia

Near InfraRed Spectroscopy (NIRS) has become an extremely important analytical technique in recent years and been applied in various geoscience areas such as mineral exploration and environmental studies. It is used for studying the physico-chemical properties of earth materials by enabling the interpretation of mineral composition and the study of its variability based on the diagnostic of spectral features. In this research, the application of laboratory reflectance spectroscopy in assessing heavy metals pollution is investigated. The potential use of reflectance spectroscopy in detecting Fe-related and clay minerals as well as the quantitative characterization of pollutants is studied for the mine waste of Jalta and Bougrine in the North of Tunisia. Mining activities of lead/Zn, have led to extensive pollution. The analysis of geochemical results outlined the level and spatial pattern of pollutants concentration. Results of the study showed that a relationship exists between reflectance spectra and geochemical measures of pollutants. The Spectral interpretation of Fe-related minerals and clay minerals showed that they are related to the pollutants and can be used as indirect spectral indicators of the pollution. The Fe-minerals include: jarosite, goethite, hematite/goethite, and hematite;clay minerals and feature-less (aspectral) materials. A direct quantitative relationship between pollutants and spectral parameters shows that Pb-Zn-Mn are the best correlated with a ratio of 610/500 nm range while Ni-Cr have a best correlation with a slope around 980 nm. Outputs from Partial Least Square Regression (PLSR) confirmed these relationships and also indicated that spectral parameters and reflectance values within 400 - 2500 nm range can better predict the contamination for Mn, Pb and Zn than for Ni and Cr but not for Fe, Cu, Cd, EC and pH.

Electrostatic Separation as a Characterizing Tool for the Insulation of Conductive Mineral Particles

This work deals with a non-conventional use of a drum-type electrostatic separator. Indeed, the electrostatic separation process is used as a tool to evaluate the efficiency of different formulations of insulating coatings surrounding coarse and irregular conducting mineral particles. Our analysis is based on the change of the particle’s distribution in the conductive and the non-conductive pans after the electrostatic separation process. Different coating formulations were tested and we found that only hydrophobic components have to be used and that a composite formulation must be considered to sufficiently increase the coating thickness. Viscous hydrophobic oil combined with talc is a particularly relevant coating formulation for insulating hematite or ilmenite particles. The viscosity of the binder plays a crucial role as it guarantees the necessary cohesion of the coating itself. To evaluate the required thickness to obtain efficient insulating capabilities for the coating surrounding coarse and irregular mineral particles, we linked the experimental volume ratio between the coating and the particles and the theoretical ratio. The experimental volume ratio is calculated using the weights of all the materials used and their respective densities. Whereas, the theoretical one is calculated using the volume the mineral particles would have, considering them all identical, spherical, with a smooth surface and the volume of the coating being uniform with the same thickness on each mineral particle. We found that an efficient insulating coating for hematite particles means a thickness of 9.5% of the average mineral radius, ranging from 125 μm to 1250 μm, resulting in an equivalent insulating thickness of about 48 μm for particles of around 1 mm in diameter. Interestingly, all results originate from the analysis of the change occurring in the particle’s distribution in the different collecting pans of an electrostatic separator.

Effects of electrostimulation and administration of succinylcholine on the expression of Fos protein in mesencephalic periaqueductal gray matter of rats after simulated weightlessness

BACKGROUND： Expression of Fos in neurons of periaqueductal gray （PAG） is used to reflect the excitability. However, changes of expression of Fos in neurons of PAG are caused by injured electrostimulation after simulated weightlessness, and the relationship between pretreatment and injection of succinylcholine has not been determined yet. OBJECTIVE ： To investigate the changes of expression of Fos in PAG induced by injured electrostimulation pretreatment and injection of succinylcholine at 2 weeks after simulated weightlessness.DESIGN： Observational and controlled animal study.SETTING： Department of Physiology, Medical School, Xi＇an Jiaotong University; Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education. MATERIALS： A total of 24 adult female SD rats, of clean grade and weighing 180-220 g, were selected in this study. METHODS： The experiment was completed in the Experimental Animal Center of Xi＇an Jiaotong University.① All rats were randomly divided into 2 groups according to body mass： simulated weightlessness group and control group with 12 in each group. And then, each group was also divided into 3 subgroups： electrostimulation group, succinylcholine-pretreatment group and succinylcholine-injection group with 4 in each subgroup. ②The model of weightlessness was simulated by tail-suspended female rats, which were described and modified by Cheng Jie. Rats in normal control group were given the same interventions as simulated weightlessness group except for tail-suspended. ③ Experimental method： The rats in electrostimulation group were given nociceptive stimulus by a pair of subcutaneous electrodes inserted into 1 and 5 claw of left hindlimb. The stimulus （current： 10 mA; duration： 1 ms; interval： 1 s） lasted for 30 minutes. The rats in succinylcholine-pretreatment group received stimulus after intravenous administration of succinylcholine, rats in succinylcholine-injection group were not given stimulus, just received succinylcholine. ④ All rats were perfused and fixed after 2 hours from the end of stimulation. The brains were removed, and serial frozen sections of midbrain were stained using immunocytochemical method, observed and taken photos under light-microscope. The number and morphological characters of Fos-immunoreactive （Fos-IR） neurons in ventrolateral part of PAG were investigated. MAIN OUTCOME MEASURES： The alterations in number and morphological characters of Fos-IR neurons in ventrolateral PAG of all rats.RESULTS： A total of 24 rats were involved in the final analysis. ① The morphological changes of Fos-IR neurons： The expressions of Fos in ventrolateral part of PAG were observed in both control and simulated weightlessness groups rats after being given nociceptive stimulus. As compared with control group, Fos-IR neurons in simulated weightlessness group were dyed lightly, cellular integrity was impaired, and cellular verge was unclear. ② The numbers of Fos-IR neurons： In control group, the numbers of Fos-IR neurons in ventrolateral part of PAG in simulated weightlessness group were obviously lower than succinylcholine-pretreatment group, but obviously higher than succinylcholine-injection group （46.94±3.38, 71.06±8.96 and 35.04±4.62, respectively, P 〈 0.05）. In 14-day simulated weightlessness group, the numbers of Fos-IR neurons in electrostimulation group were also obviously lower than succinylcholine-pretreatment group, and obviously higher than succinylcholine-injection group （27.77±3.27, 32.91±2.99 and 11.75±1.00, respectively, P 〈 0.05）. The numbers of Fos-IR neurons in all subgroups in control group were obviously higher than those subgroups in simulated weightlessness group. Compared with electrostimulation group, the percentage of expression of Fos in ventrolateral part of PAG responsed to nociceptive stimulus after administration of succinylcholine （SCH） was increased to 51.83% in control group and 18.51% in simulated weightlessness group.CONCLUSION ：① The expression of Fos in neurons in ventrolateral part of PAG were increased by the pretreatment of SCH before nociceptive stimulus.② Nociceptive stimulus could increase the expression of Fos in neurons in ventrolateral part of PAG. ③ The numbers of Fos-IR neurons in ventrolateral part of PAG were decreased obviously after 2-week simulated weightlessness.

Effect of Cooking Condiments on the Mass Loss of Artisanal Aluminum Cooking Utensils: The Case of Congo—Brazzaville

Corrosion of cookware is a growing concern for the durability of materials. A rapidly emerging theme that is one of the major current societal challenges at the interface of environmental and health issues. In this present work, the corrosion of aluminum in food environments (salt water and fresh tomatoes) was studied. The three aluminum utensils were purchased in the various workshops in Brazzaville (Republic of the Congo). The weight loss method followed the effect of cooking media on cookware, X-ray diffraction (XRD) and fluorescence (XRF) are two methods used to characterize alloys. XRF analysis indicates that the samples consist of aluminum as a basic element. XRD reveals that the essential building blocks of cookware samples are aluminum, silicon, iron, copper, magnesium and zinc. Finally, gravimetric measurements are carried out to assess the mass losses of samples of artisanal kitchen utensils when cooking food. Aluminum is found to be sensitive in TF and OS media.

Evaluation of Mineral Elements Content of Senegal Fruits

This study determined mineral value and antioxidant activity of Senegal fruits for contributing to improving healthy diet and preventing some chronic diseases. Mineral element contents of Dialium guineense, Landolphia heudelotti, Mangifera indica, Cyperus esculentus and Saba senegalensis, which are widely available and consumed, were studied. The results by ICP-OES spectrophotometry after acid mineralization showed highest levels of (per 100 g fruits), calcium (158 mg), potassium (1018 mg), magnesium (532 mg), zinc (26 mg) with juice of Landolphia heudelotti fruit pulp. Mangifera indica pulp is richer in sodium (89 mg), phosphorus (556 mg), sulphur (384 mg) and silicon (110 mg). Dialium senegalensis pulp is richer in iron (23 mg) and manganese (19 mg). Lyophilized Cyperus esculentus rhizomes analyzed by atomic absorption spectrophotometry gave highest concentrations of (per 100 g fruits), calcium (2550 mg), potassium (11,843 mg) and magnesium (7669 mg) but sodium content (22 mg) is lower. In vitro antioxidant activity evaluation with the DPPH radical showed for 10 mg/ml concentration, highest inhibition percentage for Saba senegalensis 4.03%, followed by Landolphia heudelotti and Dialium guineense, which were significantly similar 2.29% and 2.20% respectively, Mangifera indica 1.7% and finally Cyperus esculentus 0.5%, but much lower compared to the ascorbic acid equal to 96.32% used as a reference.

Structural geochemistry of gold mineralization in the Linglong-Jiaojia district, Shandong Province, China

The Linglong-Jiaojia district is one of the most important regions containing gold deposits in China. These gold deposits can be divided into: a) the pyrite-gold-quartz vein type (Linglong type), which is controlled by brittle-ductile to ductile deformation structures, and b) the alteration-zone type (Jiaojia type), characterized by small veinlets, or the disseminated type recognized in brittle shear zones. Lode gold deposits in the Jiaojia area occur in NE brittle fracture zones, formed in a dominantly simple shear deformation regime, mainly in thrust attitude with a minor sinistral strike slip component. In the Linglong area, the lode gold deposits are located at the intersection of three types of structures: NNE and NE brittle-ductile fault zones and the ENE ductile reverse shear zone in the south of the area. The structural characteristics of these brittle shear zones are consistent with a tectonic NNW-SSE principal stress field orientation. Similar stresses explain the ENE Qixia fold axes, the Potouqing and several other ENE reverse ductile shear zones elsewhere in the region, the Tancheng-Lujiang fault zone and its subsidiaries in the vicinity of the Linglong-Jiaojia district, as well as the southern ENE suture zone north of Qingdao. Therefore these structural systems occurred as part of different major tectonic events under NNW-SSE compression principal stress fields in the area. Gold deposits are hosted in smaller-scale structures within the brittle fault zones and brittle-ductile shear zones. Although ore bodies and, on a smaller scale, quartz ore veins often seem to be randomly oriented, it is possible to explain their distribution and orientation in terms of the simple shear deformation process under which they were developed. The progressive simple shear failure is characterized by various fracture modes (tension and shear) that intervene in sequence. The tension and shear fractures are influenced by the stress level (depth of burial beneath the paleosurface) in their structural behavior, show variable dilatancy (void openings) and extend on all scales. By making use of these characteristics, a progressive failure analysis can be applied to predicting the shape and extent of ore bodies as well as the styles of mineralization at any given location.

Characteristics of mineral element content of alpine vegetation in permafrost region on Qinghai-Tibetan Plateau

The content characteristics of 16 elements （Al, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sr, and Zn） in 23 plant species collected from the Qinghai-Tibetan Plateau permafrost region were investigated using ICP-OES. Results show that the average contents of Ca, K, Mg, Fe and P were higher than 1,000 mg/kg, those of Al, Na, Zn and Cr ranged between 10-1,000 mg/kg and those of Cu, Li, Pb and Mo were less than 10 mg/kg. The levels of Al, Ca, K, Mg and Na were within the scope of the reported terrestrial plant element content, those of Sr, Fe and Cr were higher than the average of the terrestrial plants and the maximum content of Max was higher than the upper limit of the reported Mn content. The main character of the element content was of the Ca〉K type, however, in terms of Cyperaeeae species the element content character was K〉Ca type. The contents of Ca, Li, Mg and Sr in Gramineae and Cyperaeeae species were higher than those in other species and the contents of Ca, K, Mg, Fe, E A1 and Na in all collected plants were higher than those of other elements. Zn had weak variability with the lowest coefficient （i.e., 7.81%）, while other elements had strong variability. The ratio of maximum content to minimum content indicated Ca and K had less change than other elements in the Qinghai-Tibetan Plateau permafrost region. Element content of alpine vegetation in the Qinghai-Tibetan Plateau permafrost region mainly shows a positive correlation, among which the correlation coefficient between Al and Pb, Al and Fe, Mo and Cr, Pb and Fe, Sr and Li were higher than 0.9, and negative correlation had no statistical signifi- cance. The correlation between Al and Fe, Mg, Mn in the Qinghai-Tibetan Plateau permafrost region were consistent with that reported in Kunlun Mountains.

Simultaneous Determination by HPLC-UV Vis of Tartrazine and Sunset Yellow in Soft Drinks Sold in Benin

The use of dyes such as tartrazine (E102) and sunset yellow (E102) in food, beverages and health products for technological and commercial purposes is common. The adverse effects caused by these dyes, such as allergies and hyperactivity disorder have been reported, especially in children. In the present study, a chromatographic method was developed and validated for simultaneous determination of tartrazine and sunset yellow. The chromatographic separation was performed on a Lichrocart® C18 column (125 × 4.6 mm;5 μm) with a security Guard-C18 column (4 × 2.0 mm, 5 μm;Phenomenex, Torrance, CA, USA) maintained at 30°C. The mobile phase consisted of a mixture of acetonitrile/ammonium acetate buffer pH 6.8 in gradient mode with a flow rate of 1 mL/min. The injection volume was 10 μL. The detection wavelength was set at 455 nm. The parameters of specificity, linearity, precision, repeatability, accuracy and sensitivity were examined for validation. The developed method is linear in the range of 1 μg/mL to 100 μg/mL with a R2> 0.998. The intra-day and inter-day precisions (RSD) were less than 0.6% and 3.1% respectively. The detection limit was 0.03 μg/mL and the quantification limit was 0.1 μg/mL. The retention time of tartrazine was 2.86 min, while sunset yellow was detected at 5.67 min. A simple, rapid, accurate and robust HPLC/UV-Visible method was developed and validated for simultaneous identification and quantification of tartrazine and sunset yellow. This developed method was successfully applied for the simultaneous determination of tartrazine and sunset yellow in soft drinks sold in Benin.

POLYGENETIC MINERALIZATION OF THE EARLY PROTEROZOIC TONGKUANGYU METAPORPHYRY COPPER DEPOSIT IN THE ZHONGTIAO MOUNTAINS OF CHINA

The Tongkuangyu porphyry copper deposit in the Zhongtiao Mountains, China, is tectonically located on the southern margin of the North China platform and on the northern margin of the Late Archean Zhongtiaoshan intracontinental rift basin. The deposit occurs in a copper-bearing formation of tuffaceous variegated sandshale-K-rich bimodal volcanic rocks of the Tongkuangyu Formation of the Late Archean Jiangxian Group, and the orebodies are localized in a transition portion between tuffaceous variegated sandshale and bimodal volcanic rocks. The host rocks consist mainly of metagranodiorite-porphyry, meta-quartz monzonite-

Efficient removal of polybrominated diphenyl ethers from soil washing effluent by dummy molecular imprinted adsorbents: Selectivity and mechanisms

Surfactant enhanced elution is an effective method for removing hydrophobic organic pollutants from soils.The key to the development of leaching technology is selective removal of targeted pollutants in soil washing effluent and recycling of surfactant solutions.In this study,a molecular imprinting technique was applied to selectively sorb polybrominated diphenyl ethers(PBDEs)in soil washing effluent.The novel molecular imprinted polymers(MIPs)using different template molecules were synthesized by precipitation polymerization.Adsorption behaviors andmechanisms ofMIPs were studied through experiments and theoretical calculations.The results show that 4-bromo-4'-hydroxybiphenyl and toluene can be effective imprinting molecule for MIPs synthesis.The maximal adsorption capacity of selected dummy molecular imprinted polymer(D1-MIP)was 1032.36μmol/g,and that of part molecular imprinted polymer(P-MIP)was 981.13μmol/g.Their imprinting factors in 5 PBDEs adsorption ranged from 2.13 to 5.88,the recovery percentage of Triton X-100 can reach 99.09%,confirming the feasibility of reusing surfactant.Various PBDEs could be removed by MIPs,and Quantitative Structure Property Relationship analysis revealed that PBDEs’molecular volume,planarity,polarity,and hydrophobicity have major influences on their adsorption performance.DFT calculation revealed that Van derWaals force and hydrogen bonding played important roles during selective adsorption.These results can provide effective theoretical guidance for surfactant enhanced soil elution in practical engineering applications.

深部软岩巷道围岩与锚喷U型钢支护结构相互作用研究

收敛-约束法(特性曲线法)是将理论解析、现场实测、工程经验相结合的一种地下工程结构设计方法,是目前分析围岩-支护相互作用关系及开展支护优化设计的常用方法。基于收敛-约束法的基本原理,总结给出了经典的支护特征与支护结构变形方程,理论计算获得了喷射混凝土、锚杆(索)、U型钢支架等支护结构的支护特征曲线,分析了支护结构的几何尺寸(直径、长度)、间排距、材料强度等参数对支护压力的影响特征;随着喷射混凝土厚度及强度等级的增加,喷射混凝土提供的支护刚度和支护压力逐渐增大;随着锚杆(索)直径、长度、杆体材料强度的增加及间排距的减小,锚杆的支护压力显著增加;U型钢支架的排距越小及材料强度越大,其提供的支护压力越大。采用FLAC^(3D)内嵌的莫尔库伦应变软化本构模型,建立了考虑岩石峰后应变软化与扩容特性的深部软岩巷道数值分析模型,计算获得了不同应力状态下巷道纵剖面变形曲线、围岩特征曲线,分析了锚喷、锚杆(索)喷、锚喷U型钢等3种联合支护技术对深部巷道围岩大变形控制的适用性,验证了锚喷U型钢联合支护技术应用于深部巷道支护工程的可行性。考虑岩石峰后应变软化与扩容特性的应变软化本构模型和经典的莫尔库伦本构模型的数值模拟结果相差较大,采用莫尔库伦本构模型的数值模拟结果保守,支护结构提供的支护压力无法满足深部巷道稳定性控制要求,支护后巷道围岩变形较大甚至会发生冒顶、片帮等安全事故。

一种基于暗亮通道分割融合的低照度环境图像去尘雾及增强方法

受煤矿井下粉尘、水雾和低照度环境影响,对皮带运输系统的监测图像精准识别极为困难。针对现有去尘雾方法的图像处理结果和效率欠佳的问题,提出一种基于暗亮通道分割融合的低照度环境图像去尘雾及增强方法。首先利用阈值分割结合伽马变换修正通道差,解决因低照度环境影响导致的尘雾浓度较大区域与其他区域间像素值差异不明显的问题,修正后通过引导尘雾图像做引导滤波得到更加符合实际情况的全局大气光强;然后为解决暗通道先验在尘雾浓度较大区域失效问题,引入亮通道先验进行补充,使用通道分量来辅助暗通道及亮通道透射率融合,避免因多次分割而导致的边缘像素归属问题;最后将去雾后RGB图像转至HSV空间,对亮度分量进行直方图均衡化并将均衡化前后的亮度分量进行加权融合,采用客观指标评价,选择最优聚合权值进行聚合,同时考虑去雾过程中饱和度损失和亮度分量与饱和度分量间的相关性提出饱和度自适应矫正函数,对图像饱和度进行矫正,色调分量保持不变,随后将图像转回至RGB空间,得到亮度适中、信息保留丰富和色彩鲜艳的图像;为验证所提方法的有效性,采用主观视觉、客观指标和目标检测精度及置信度进行算法对比,实验结果表明所提方法在上述4个指标上均优于被对比算法,其图像细节保留丰富,图像视觉观感更佳。

RPC外包方钢管混凝土柱轴压受力性能研究

为了研究活性粉末混凝土(Reactive powder concrete,RPC)外包方钢管混凝土柱的轴压受力性能,以RPC厚度和长细比为参数,对6根构件开展轴压试验研究,探讨该类组合柱的破坏模式、受力机理、套箍效应和承载力。试验结果表明:外层RPC可为内部方钢管混凝土柱提供较强的约束力,在受力后期套箍效应凸显。随着RPC厚度的增加,组合柱的承载力逐渐提高;随着组合柱长细比的增大,虽然其弹性刚度和承载力逐渐降低,但延性改善。采用ABAQUS软件建立RPC外包方钢管混凝土柱的有限元模型,分析RPC强度、RPC厚度、钢管强度等级、含钢率、内部混凝土强度和长细比等参数对组合柱承载力的影响规律,可得方钢管混凝土柱发挥系数的变化幅值为0.78~1.01。在试验研究、有限元参数分析和理论探讨的基础上,借鉴钢管混凝土结构技术规范,提出了RPC外包方钢管混凝土轴压短柱和长柱的承载力简化计算方法,公式计算值与已有数据样本吻合良好。

脂滴功能及其与卵母细胞成熟和胚胎发育的关系研究进展

脂滴不仅是真核细胞内贮存甘油三酯和胆固醇酯等中性脂质的重要细胞器,也是细胞代谢和细胞器质量控制的中心调控者,参与细胞能量代谢、类固醇激素合成、内质网应激、线粒体功能以及生物膜结构形成等过程的调控。目前认为脂滴合成于内质网,并以出芽的方式进入细胞质。脂滴是呈动态分布的细胞器,其数量、大小以及分布受细胞获得营养物质和代谢状态影响。众所周知,哺乳动物卵母细胞含有脂滴,且卵母细胞中含有足够数量的脂滴与卵母细胞成熟和早期胚胎发育密切相关。更重要的是,最近的研究表明,脂滴在胚胎附植着床过程中发挥了至关重要的作用,即使卵母细胞中脂滴含量较低的哺乳动物,维持适量的脂滴对早期胚胎发育也很重要。因此,本文综述了脂滴的合成与分布,分析了脂滴的主要功能,重点阐述脂滴在动物卵母细胞成熟和早期胚胎发育期间的关键作用,并讨论脂滴卵母细胞和胚胎内脂滴含量与胚胎滞育持续时间的关系,以期为通过调控脂滴代谢而增强卵母细胞质量和胚胎发育能力,进而提高动物繁殖性能提供理论基础。

基于MGMA的随钻陀螺仪误差在线补偿

针对随钻测量MEMS陀螺仪输出精度低的问题,提出一种基于磁-重力蜉蝣算法(MGMA)的陀螺误差在线补偿方法。首先,分析随钻陀螺误差来源并推导出误差补偿模型;其次,利用MEMS加速度计无累积误差的特点,根据重力向量叉乘得到向量夹角作为目标函数;此外,考虑到实际钻进时强振动和冲击对加速度计输出的不利影响,利用MEMS磁强计抗振的特点,设计磁模值相对误差约束条件。然后,在MA基础上,针对随钻恶劣环境影响下的陀螺误差参数不断变化问题,根据陀螺和磁强计输出之间的关系自适应确定搜索上下界;并利用重力模值相对误差设计惯性权重,平衡算法的全局探索和局部开发能力;最后,利用磁-重力模值相对误差在子代中引入变异扰动策略,减小陷入局部最优的可能。实验结果表明,经MGMA补偿后的陀螺输出误差明显减小,井斜角误差由9.75°降低至1.52°,且相比于PSO和MA算法具有速度快、精度高的优势。

高潜水位矿区土地利用和碳储量时空变化规律与预测

高潜水位矿区采矿活动及城镇化发展会导致土地利用类型明显变化,进而影响矿区的固碳能力。采用潘谢矿区2002-2021年5期土地利用数据,利用FLUS(Future Land Use Simulation)模型,选取了采矿、社会经济和气候环境等方面数据作为驱动因子,分别预测了自然发展和生态保护两种情景下2028年土地利用变化,再结合InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs)模型,计算了潘谢矿区2002-2021年的历史碳储量以及2028年不同情景下的未来碳储量,并对潘谢矿区碳储量的时空变化特征进行了分析。结果表明:(1)2002-2021年潘谢矿区土地利用变化表现为耕地不断减少,湿地和建筑用地持续增加,其中耕地减少了147.93 km^(2),湿地和建筑用地分别增加了71.01 km^(2)和75.76 km^(2)。在此期间,潘谢矿区碳储量减少了1.62×10^(5)t,减少幅度为3.83%,其中在2018-2021年碳储量下降最快。(2)预测结果显示,2028年2种情景下研究区内土地利用变化均为湿地和建筑用地持续增加,耕地不断减少。但相较于自然发展情景,生态保护情景下矿区内耕地受到保护,面积有所增加,湿地和建筑用地的增长减缓。与2021年相比,自然发展情景下的碳储量减少了0.74×10^(5)t,生态保护情景下的碳储量减少了0.53×10^(5)t。研究结果表明,受采煤沉陷和城镇发展影响,沉陷湿地和建筑用地扩张导致耕地减少是碳储量下降的主要原因,采取生态保护措施能够在一定程度上减缓碳储量的下降。

毛红椿与杉木混交造林早期生长效果分析

于2019—2023年,在福建省三明市沙县区高砂镇林场开展毛红椿与杉木不同比例混交及不同密度造林试验,研究混交树种的树高、地径、胸径、冠幅、单株立木材积和林分蓄积等生长性状的早期效果。结果表明,5年生的毛6杉4、初植密度为3330株·hm^(-2)(株行距2 m×1.5 m)的混交林中,毛红椿树高、地径、胸径、冠幅、单株立木材积和林分蓄积、林分总蓄积量均最高,分别达6.97 m、8.77 cm、7.13 cm、3.10 m、0.0173 m^(3)、34.60 m^(3)·hm^(-2)、48.03 m^(3)·hm^(-2),比平均值高出38.84%、21.30%、25.09%、42.86%、88.04%、1.66倍、1.01倍;杉木的树高、单株立木材积和林分蓄积均最高,分别达5.33 m、0.0173 m^(3)、34.68 m^(3)·hm^(-2);比平均值高出22.53%、1.08倍、2.18倍。毛2杉8、初植密度2505株·hm^(-2)(株行距2 m×2 m)的混交林中,杉木的地径、胸径和冠幅均最高,分别达10.67 cm、8.17 cm、2.67 m,分别比平均值高出52.60%、52.36%、47.33%。结果表明,在毛红椿与杉木混交造林时,宜用较大密度种植,初始造林密度适合在2505~3330株·hm^(-2);且相应加大毛红椿的比例。

国产胶合木柱生产碳排放量测算及碳减排研究

碳排放量是评估胶合木生产环境影响的重要指标,现有碳排放数据多引用国外和基于理想模型测算,难以真实反映我国当下生产条件碳排放水平。以赤松(Pinus densiflora)胶合木柱为研究对象,基于现场调研分析胶合木柱生产工艺过程的碳排放源,从辅料、能源两个方面建立碳排放边界模型和物料清单,计算产品碳排放量,并分析生产过程碳排放特征,从生产工艺角度提出减碳方式。结果表明:胶合木柱的碳排放量为330.16 kgCO_(2)e/m^(3);锯材生产阶段、胶合木及木柱制作阶段的碳排放量分别占总量的78.5%和21.5%;窑干、接长、施胶、搬运经优化后,可实现碳减排44.3%,优化效果显著。

基于三元DEM的露天煤矿封闭壳状包络体素建模研究

传统地质模型受自身结构性质和布尔运算效率的局限,限制了采矿模型的生成,无法满足露天矿大规模物料规划问题的需求。针对上述问题,对开采体块段模型及采矿模型进行了定义,并提出了一种基于三元DEM的露天煤矿封闭壳状包络体素快速建模方法,即煤岩模型的顶面、底面和侧面DEM建模,三元DEM经固化后即可生成煤岩体对应的封闭壳状包络体素模型。该模型介于实体模型和块体模型之间,能够保障算量精度,同时具有较高的布尔运算效率,可以现实定点、定向的尺寸和结构剖切,在传统算量地模的基础上,通过特定的结构定义,丰富剥采程序和工艺参数等技术指标属性,定制专属的采矿模型,更好地服务于露天矿物料流规划、采剥生产计划动态优化等问题。