Degradation of Extraction from Seaweed and Its Complex with Rare Earths for Organophosphorous Pesticides

On the basis of several experiments carried out in China, it was proved that both seaweed liquid fertilizer and rare earth （RE） could promote the growth of crops and increase their yield. The effects of extraction from seaweed and its complex with RE on the degradation of organophosphorous pesticides and the yield of vegetables were investigated. The resuits showed that the extract and its complex with RE could degrade organophosphorous pesticides in neutral solvent. The residues of the pesticides treated by the extract decreased by 96.88 %, 52.30%, 49.52%, and 22.88 %, respectively, for chlorpyrifos, dichlorvos, omethoate, and dimethoate, and those by the complex decreased by 95.99%, 54.23%, 48.79%, and 25.66%, respectively, when compared with the control. The residues of chlorpyrifos and dimethoate in spinach sprayed with the complex were decreased by 90.64% and 76.56%, respectively, compared with those in spinach from control plots when the interval between spraying and sampling was 8 d. The fresh weight of brassica chinensis and cabbage increased by 28.62% and 18.72%, and their dry weight increased by 44.49% and 14.74%, respectively, compared with those of the controls. The chlorpyrifos and dimethoate residues in brasscia chinese were decreased by 36.36% and 50.00%, respectively, and their rate of decrease in cabbage was 40.00% and 75.00%, respectively, on 5th day after spraying with the complex, when compared with those in the vegetable from control. These results suggest that this complex can increase the agricultural productivity and reduce the use of pesticide residues in the production of vegetables.

Degradation of bond between steel bar and freeze-thaw concrete after electrochemical chloride extraction

The effect of electrochemical chloride extraction （ECE） on bond strength between steel bar and freeze-thaw concrete contaminated by chloride was experimentally investigated for beam specimens with dimensions of 100 mm × 100 mm × 400 ram. During the experiment, 3% NaC1 （vs mass of cement, mass fraction） was mixed into concrete to simulate chloride contamination, and the specimens experienced 0, 25, 50, 75 freeze-thaw cycles before ECE. In the process of ECE, different current densities and durations were adopted. It is indicated that the bond strength between reinforcement and concrete decreases with the increase of freeze-thaw cycles; the more the current and the electric quantity of ECE are, the more the loss of bond strength is; and the largest loss is up to 58.7%. So, it is important to choose proper parameters of ECE for the reinforced concrete structures contaminated by chloride and subjected to freeze-thaw cycles.

Degradation Dynamics and Residue Analysis of Flubendiamide in Cabbage and Soil by Liquid Chromatography-Tandem Mass Spectrometry with Dispersive Solid Phase Extraction

To formulate a scientific basis for a reasonable spray dose and safe interval period of 20% flubendiamide water dispersible granule (WDG) on controlling vegetable pests, degradation dynamics of flubendiamide in cabbage and soil was analyzed in this study. Dissipation and residue of flubendiamide in 20% flubendiamide WDG in cabbage and soil under field conditions were investigated by liquid chromatography-tandem mass spectrometry with dispersive solid phase extraction. Results showed that the degradation dynamic equations of flubendiamide in cabbage and soil were based on the first-order reaction dynamic equations. The half-lives of the degradation of flubendiamide were 3.51 d to 3.96 d and 3.43 d to 3.87 d in the cabbage of Yangzhou and Jingzhou, respectively, and 4.42 d to 5.13 d and 4.37 d to 4.99 d in the soil of Yangzhou and Jingzhou, respectively. The terminal residues of flubendiamide in the cabbage of Yangzhou and Jingzhou were 0.0247 mg·kg-1 to 0.0393 mg·kg-1 and 0.0225 mg·kg-1 to 0.0273 mg·kg-1, respectively, when 20% flubendiamide WDG was applied at a dose of0.050g·m-2. Flubendiamide is safe to be applied in cabbage fields at the recommended dose.

Effects of Rice Straw Silicification and Characters of Extraction Biogenic Silicon on the Degradation of Fibrous Components in Rice Straw

Straw of seven rice varieties with early-, middle- and late maturity was collected from Huazhong Agricultural University in Hubei. A study was carried out for rice straw in the aspects of the characters of straw silicification and extraction biogenic silica (EBSi), the relationship between characters of EBSi and kinetic characteristics of degradation of fibrous components in fistulated cows, as well as the effect of urea treatment on rice straw desilicification. Although total silica content (ADISi) in rice straw was similar, the efficiency of extraction biogenic silica (EEBSi) and cellulose in early varieties were significantly higher than those in middle (18.9% and 9.1 %) and late ones (26.1% and 11.2%). The degradability of EBSi and cellulose of early varieties were higher than those of middle by 70.0% and 17.5%, and of late varieties by 47.8% and 23.7% , respectively. The in sacco degradability and in vitro VFA production of early varieties were also higher than those of middle by 14.5% and 19.0%, and late by 12.9% and 14.8%. Comparing the morphological fractions of the rice straws, EEBSi, cellulose content, and in vitro VFA production were different with the order of blade < sheath < stem. A significant correlation was found between the contents of EBSi and cellulose (r= 0.86), and the two contents were remarkably correlated with the potential straw degradability (a + b) by r = 0.90 and 0.84 respectively. Therefore, EBSi in rice straw was a main factor affecting the potential degradability of rice straw, rather than the ADISi of straw. Urea treatment improved rice straw degradability, degradation rate and potential degradability by 10.8% , 27.9% , and 10.1% respectively, compared to untreated straws.

Assessment of China's economic loss resulting from the degradation of agricultural land in the end of 20th century

Land degradation is a consequence stemming from both natural processes and social economic activities. On the bases of analyzing general situation of agricultural land degradation in China, the monetary estimating methods such as market value method and shadow engineering method were used to quantitatively assess the economic loss resulting from land deterioration. Results showed that the economic loss in 1999 was 326 81 billion RMB Yuan, which accounted for 4 1% of GDP in the same year of China. If taking five items namely farmland conversion, soil erosion, salinization, decline in reservoir functions, and siltation in waterways and, comparing with that in 1992, the percentage of economic loss to GDP has increased by 1 5 in the only 7 years.

Energy loss of degrader in SC200 proton therapy facility

The proton beam energy determines the range of particles and thus where the dose is deposited. According to the depth of tumors, an energy degrader is needed to modulate the proton beam energy in proton therapy facilities based on cyclotrons, because the energy of beam extracted from the cyclotron is fixed. The energy loss was simulated for the graphite degrader used in the beamline at the superconducting cyclotron of 200 MeV in Hefei(SC200). After adjusting the mean excitation energy of the graphite used in the degrader to 76 eV, we observed an accurate match between the simulations and measurements.We also simulated the energy spread of the degraded beam and the transmission of the degrader using theoretical formulae. The results agree well with the Monte Carlo simulation.

Effects of Grassland Degradation and Re-vegetation on Carbon and Nitrogen Storage in the Soils of the Headwater Area Nature Reserve on the Qinghai-Tibetan Plateau,China

Both overgrazing and climate change contribute to grassland degradation in the alpine regions of China and negatively affect soil carbon and nitrogen pools. We quantified changes in soil organic carbon （SOC） and total nitrogen （TN） in black soil beach （BSB）. We measured SOC and TN in severely degraded and non-degraded grasslands to calculate differences in carbon and nitrogen storage, and field survey results were extrapolated to the entire headwaters area of the Qinghai-Tibetan Plateau （36.3xlos krn~） to determine SOC and TN losses from these grasslands. We also evaluated changes in SOC and TN in severely degraded grasslands that were artificially re-vegetated five, seven and nine years ago. Totally 92.43 Tg C and 7.08 Tg N were lost from the BSB in the headwater area, which was approximately 50% of the original C and N soil pools. Re-vegetation of the degraded grasslands in the headwater area would result in a gain of 32.71 Tg C in the soil after five years, a loss of 5.5a Tg C after seven years and an increase of 44.15 Tg C after nine years. The TN increased by 53.09% and 59.98% after five and nine years, respectively, while it decreased by 4.92% after seven years of re-vegetation. The results indicate that C and N stocks followed a ＂V＂ shaped pattern with re- vegetation time. Understanding plant-soil interactions during succession of artificially planting grassland ecosystems is essential for developing scientifically sound management strategies for the effectively re-vegetated BSB.

DEGRADATION OF NATURAL RESOURCES BY ENVIRONMENTAL POLLUTION——A Comparative Study Between Huizhou City and Zhaoqing City

Compared the total agricultural production (TAP) of the 5 counties in Huizhou City with that of the corresponding 5 counties in Zhaoqing City during the period from 1980 to 1996, it can be seen that the TAP growth rate of the 5 counties in Huizhou City had been a little higher than that of the 5 corresponding counties in Zhaoqing City before 1983, but has been becoming lower than the latter since 1984, and the agricultural production in Huizhou City has been gradually becoming lag behind that in Zhaoqing City since then. The TAP loss in Huizhou City kept above 3×10 8 yuan every year since 1986. Detailed investigation shows that the acid rain caused by the atmospheric pollution may be the main cause for the lower productivity of the land in Huizhou City. The atmospheric pollution arisen from rapid and extensive development of the economy in the Zhujiang(Pearl) River Delta Region has already greatly reduced the load capacity of the natural resources in Huizhou City and severely affected the sustainable development of the region.

Degradation of AZ31 and AZ91 magnesium alloys in different physiological media:Effect of surface layer stability on electrochemical behaviour

This work deals with the degradation of AZ31 and AZ91 magnesium alloys when they are exposed to three types of physiological media for seven days at 37°C:Ringer's,Hanks\and simulated body fluid(SBF)solutions.A combination of immersions tests and surface characterisation methods were employed to evaluate the attack on the surface,and the stability of the formed corrosion product layers for each alloy/electrolyte system.Measurements of the Mg-ion released into the electrolytes were also carried out in order to be correlated with the degradation of the alloys.Electrochemical impedance spectroscopy(EIS)and potentiodynamic polarisation(PDP)techniques were employed to compare the performance of the alloys in these different aggressive electrolytes.According to the obtained results,the Mg-alloys exposed to Hanks'media were the less affected,which fact was attributed to a higher stability of the corrosion products layer formed in this medium,in comparison of those formed in Ringer's and SBF solutions.In add让ion,the corrosion damage was lower for AZ91 than for AZ31 alloy in all environments due to its higher Al content.The mass loss rates calculated from both immersion tests and electrochemical methods followed the same trend for comparative purposes between alloys.

Degradation of Lix984N and its effect on interfacial emulsion

The organic phase separated from the interfacial crud provided by Dexing copper mine in Jiangxi, China, was analyzed by combined gas chromatography-mass spectroscopy. The results show that many kinds of emphiphiles containing such hydrophilic groups as carbonyl, carboxyl, sulphonyl or acylamine exist in organic phase. Conclusively, Lix984N would degrade gradually during a long-term contact with the acidic aqueous feed and strip reagents. Lix84 and nonylphenol as effective components of Lix984N degraded almost completely after long-term recycling. Lix984N degraded through such reactions as Beck.mann rearrange, hydrolysis and sulphofication. The degradation of Lix984N would deteriorate solvent extraction and disengagement performance, and result in a more stable interracial emulsion.

Kinetic Parameters of Thermal Degradation of Polymers

The derivative expressions between activation energy (E) and the temperature at the maximum mass loss rate(Tmax) and between activation energy (E) and exponent (N) were deduced in the light of Arrhenius theory. It was found that the increase of activation energy results in the decrease of exponent and the increase of Tmax. The kinetic parameters were involved in the analysis of the thermal degradation of several polymers. The degradation kinetics of these polymers well complied with the prediction of the derivative expressions for the polymer degradation with single mechanism dominated.

Rapid determination of lithium-ion battery degradation: High C-rate LAM and calculated limiting LLI

Herein,incremental capacity-differential voltage (IC-DV) at a high C-rate (HC) is used as a non-invasive diagnostic tool in lithium-ion batteries,which inevitably exhibit capacity fading caused by multiple mechanisms during charge/discharge cycling.Because battery degradation modes are complex,the simple output of capacity fading does not yield any useful data in that respect.Although IC and DV curves obtained under restricted conditions (<0.1C,25℃) were applied in non-invasive analysis for accurate observation of degradation symptoms,a facile,rapid diagnostic approach without intricate,complex calculations is critical in on-board applications.Herein,Li Ni_(0.5)Mn_(0.3)Co_(0.2)O_(2)(NMC532)/graphite pouch cells were cycled at 4 and 6C and the degradation characteristics,i.e.,loss of active materials (LAM) and loss of lithium inventory (LLI),were parameterized using the IC-DV curves.During the incremental current cycling,the initial steep LAM and LLI slopes underwent gradual transitions to gentle states and revealed the gap between low-and high-current measurements.A quantitative comparison of LAM at high and low C-rate showed that a IC;revealed the relative amount of available reaction region limited by cell polarization.However,this did not provide a direct relationship for estimating the LAM at a low C-rate.Conversely,the limiting LLI,which is calculated at a C-rate approaching 0,was obtained by extrapolating the LLI through more than two points measured at high C-rate,and therefore,the LLI at 0.1C was accurately determined using rapid cycling.

Evaluation of corrosion resistance, mechanical integrity loss and biocompatibility of PCL/HA/TiO_(2) hybrid coated biodegradable ZM21 Mg alloy

A novel PCL/HA/TiO_(2)hybrid coating on ZM21 Mg alloy substrate has been investigated for corrosion resistance, biocompatibility and mechanical integrity loss in terms of bending, compressive and tensile strength in physiological media. The prepared hybrid coating was dip coated over ZM21 from HA/TiO_(2)and PCL solutions followed by creating a microporous PCL layer by utilizing Non-solvent Induced Phase Separation(NIPS) technique. The electrochemical measurement and in-vitro degradation study in SBF after 28 days showed that the PCL/HA/TiO_(2) hybrid coating reduced H2 evolution rate, weight loss, and corrosion rate by 64, 116 and 118 times respectively, as compared to uncoated ZM21 samples. The surface studies carried out using SEM-EDX, FTIR and XRD revealed formation of highly stable 3d flower-like HA crystals with Ca/P ratio of 1.60 in the PCL micropores. This dense apatite growth effectively protected the PCL/HA/TiO_(2)hybrid coated samples to maintain the good mechanical integrity even after 28 days of immersion as compared to HA/TiO_(2)composite coated, As-polished(A/P) and As-machined(A/M) samples. The failure analysis of samples under mechanical loading were performed using SEM-BSE-EBSD.The in-vitro cellular viability of L929 fibroblast cells on PCL/HA/TiO_(2)hybrid coating was found 50.47% higher with respect to control group,whereas bacterial viability was supressed by 57.15 and 62.35% against gram-positive Staphylococcus aureus and gram-negative Escherichia coli bacterial models. The comprehensive assessment indicates PCL/HA/TiO_(2)hybrid coating as a suitable candidate to delay early degradation and mechanical integrity loss of Mg-based alloys for devising biodegradable orthopaedic implant.

Comparing Two Automated Methods of DNA Extraction from Degraded Skeletal Remains

DNA extraction from degraded skeletal samples is often particularly challenging. The difficulty derives from the fact that variable environment has a significant effect on DNA preservation. During the years 2002-2015 unidentified degraded skeletal remains were accumulated at our institute, National Institute of Forensic Medicine (NIFM), most of them with none or partial DNA profile. As new methods rapidly emerge, we revisited these samples with partial DNA profiles in the hope to add additional alleles and eventually be able to identify these previously unidentifiable samples. We have chosen to use these samples to compare two automated methods: Prepfiler Express BTA (Applied Biosystems) and QIAcube (Quiagen), in hope of acquiring a more complete DNA profile and eventually make new identifications possibly comparing these profiles with missing person database. In both methods, a preparation step is required, after which the samples undergo automatic DNA extraction. The two protocols are based on different extraction methods. Fresh or non-problematic bone samples as the positive control gave the same results in both methods. In the degraded skeletal samples, the results were significantly better using the QIAcube method in our hands, but since degraded samples are highly variable the combination of both methods could be useful to receive better and more reliable profiles.

Eco-Friendly Production of Silver Nanoparticles from Peel of Tangerine for Degradation of Dye

Green chemistry methods for production of nanoparticles have many advantages, such as ease of use, which makes the methods desirable and economically viable. The aim of the present work was to green synthesise silver nanoparticles (SNPs) using aqueous tangerine peel extract in different ratios (2:1, 1:1, 1:2). The formed SNPs were characterised using ultraviolet-visible (UV-Vis) spectrophotometry, and transmission electron microscopy (TEM). The UV-Vis spectra showed that the highest absorbance was observed when the ratio of peel tangerine extract to silver nitrate solution was 1:2. The transmission electron micrographs showed the formation of poly dispersed nanoparticles. It was found that the average diameter of the nanoparticles was 30.29 ± 5.1 nm, 16.68 ± 5.7 nm, and 25.85 ± 8.4 nm, using a tangerine peel solution and silver nitrate solution ratio of 2:1, 1:1, and 1:2, respectively. The formed SNPs were evaluated as catalysts for methyl orange dye degradation, and the results confirmed that SNPs can speed up the degradation of the dye.

Characterization of Forest Degradation beyond Canopy Cover Change in Mau Forest, Kenya

Monitoring Forest degradation is evidence enough to show a country’s commitment to monitor the forest trend both for national and local decision-making and international reporting processes. Unlike deforestation which is easier to point out, monitoring forest degradation is quite a challenge since there is no universal definition and thus no clear monitoring methods apart from the canopy cover change. This research, therefore, sought to look at the degradation trends in the Mau forest complex between 1995-2020 with the aim of finding out whether monitoring canopy density changes over time and quantifying these changes in terms of biomass loss could be a good approach in monitoring forest degradation. Forest Canopy Density (FCD) model was adopted focusing on using vegetation indices describing biophysical conditions of Vegetation, Shadow and Bareness to monitor changes in canopy density as a parameter for describing forest degradation in the forest blocks of Maasai Mau and Olpusimoru in Mau forest complex. Results indicated how different vegetation indices responded to changes in the vegetation density and eventually changes in the canopy density values which were converted in terms of biomass loss. The forest Canopy Density model proved to be a good tool for monitoring forest degradation since it combines different biophysical indices with different characteristics capturing what is happening below the canopy.

cSi Photovoltaic Modules, Main Degradation Factors Case Study: La Puna (Argentina)

This paper presents an analysis of the power loss of a set of photovoltaic modules exposed for more than fifteen years to solar radiation and other environmental factors. The study covered modules installed in 1989 and concluded with modules installed in 2004 (to 2009). Many of them were located in places high above the sea level and with high values of ultraviolet radiation. It is known that this power loss is caused by various factors: loss of optical properties of the protective glass, loss of transmittance of the encapsulation material (EVA), increase in series resistance, decrease in shunt resistance as well as other factors not analyzed in this study. The contribution of each of these factors to the power loss is measured and discussed in this analysis.

Automatic road extraction framework based on codec network

Road extraction based on deep learning is one of hot spots of semantic segmentation in the past decade.In this work,we proposed a framework based on codec network for automatic road extraction from remote sensing images.Firstly,a pre-trained ResNet34 was migrated to U-Net and its encoding structure was replaced to deepen the number of network layers,which reduces the error rate of road segmentation and the loss of details.Secondly,dilated convolution was used to connect the encoder and the decoder of network to expand the receptive field and retain more low-dimensional information of the image.Afterwards,the channel attention mechanism was used to select the information of the feature image obtained by up-sampling of the encoder,the weights of target features were optimized to enhance the features of target region and suppress the features of background and noise regions,and thus the feature extraction effect of the remote sensing image with complex background was optimized.Finally,an adaptive sigmoid loss function was proposed,which optimizes the imbalance between the road and the background,and makes the model reach the optimal solution.Experimental results show that compared with several semantic segmentation networks,the proposed method can greatly reduce the error rate of road segmentation and effectively improve the accuracy of road extraction from remote sensing images.

热强化气相抽提联合微生物降解技术在加油站场地修复中的应用

以某加油站石油烃污染场地修复工程为案例,根据场地污染状况和修复要求,采用热强化气相抽提联合微生物降解技术进行原位修复。修复区域设置10口抽提井,5口注入井和8口监测井。首先应用气相抽提技术除去土壤中的挥发性有机物,修复20 d后,场地石油烃浓度低于国家标准GB 36600第二类用地筛选值;然后进行热强化气相抽提操作,将土壤中部分半挥发性有机物抽提出来;最后向土壤中注入高效降解菌,进一步除去土壤中残留的污染物,生物降解进行45 d后,土壤石油烃浓度低于第一类用地筛选值,实现修复目标。修复结果表明,该联合修复技术高效、绿色,修复过程可为同类场地修复提供工程借鉴。

基于改进YOLOv5的复杂场景电动车头盔检测方法

佩戴电动车头盔是安全骑行的重要保障,对电动车驾乘人员佩戴头盔进行有效检测在保障驾乘人员安全方面具有重要意义。电动车头盔检测中存在目标之间相互遮挡、复杂背景干扰、头盔目标小等问题,现有方法尚不能满足复杂场景下电动车头盔检测的要求,因此,提出一种改进YOLOv5的复杂场景电动车头盔识别方法。首先,提出一种新的主干网络结构ML-CSPDarknet53,增强网络的特征提取能力,引入轻量级上采样算子CARAFE,利用特征图语义信息扩大感受野;其次,搭建坐标卷积CoordConv模块,增强网络对空间信息的感知能力,并将WIoU v3作为边界框损失函数,降低低质量样本对模型性能的不利影响;最后,构建了内容丰富的头盔检测数据集对改进算法进行验证。实验结果表明,改进后算法相较于原算法在精确度、召回率、mAP@0.5、mAP@0.5:0.95上分别提升了2.9%、3.0%、3.4%和2.2%,并且性能优于其他主流检测算法,满足复杂道路交通场景下电动车驾乘人员头盔检测的任务要求。