沼液过量还田对土壤环境容量及玉米生长的影响

以沼液过量还田为前提,探讨沼液不同还田量对土壤环境质量和玉米生长发育的影响,提出沼液还田的安全容量。根据目标需氮量确定沼液施用量,共设5个处理:未施加任何肥料(N0 t/hm^(2),CK);1倍氮当量沼液(N 0.885 t/hm^(2),1N);2倍氮当量沼液(N 1.770 t/hm^(2),2N);3倍氮当量沼液(N 2.655 t/hm^(2),3N);4倍氮当量沼液(N 3.540 t/hm^(2),4N)。结果表明,沼液还田可显著增加玉米田土壤中Cu、Zn含量,1N处理为最佳安全容量,2N、3N、4N处理土壤存在Cu、Zn污染风险,其中,玉米完熟时4N处理Cu、Zn含量分别超出风险筛选值10.96%和10.36%,风险最大。与对照相比,沼液还田显著增加玉米苗期土壤中可溶性盐含量,提高土壤的pH值,但随着生育期的延长,可溶性盐含量和pH值呈下降趋势;至玉米的完熟期,1N、2N、3N、4N处理土壤可溶性盐含量比对照分别高出30.59%、52.16%、72.35%、108.63%,土壤pH值比对照分别高出3.95%、6.41%、9.05%、13.65%。所有处理的蛔虫卵死亡率均为100%,故沼液还田不存在蛔虫卵存活的安全风险,但3N与4N处理土壤存在大肠杆菌污染的风险,完熟期这2个处理土壤的大肠杆菌菌群含量分别为20、30个/g。沼液还田可增加玉米产量和改善玉米品质,以3N处理产量最高和品质最优,与对照相比,粗蛋白、粗脂肪、粗淀粉含量分别提高了19.82%、89.01%、11.31%,产量是对照的2.08倍。综合分析认为,以玉米产量最大和品质最优为优先目标时,3N处理为最优,以土壤环境安全容量为优先目标时,1N处理为最优。

沼液与化肥配施对耕层土壤化学性状及玉米产量品质的影响

以玉米品种登海605为试材,研究沼液与化肥配施对耕层土壤化学性状及玉米产量、品质的影响。基于等氮原则,共设6个处理,即处理1:CK(空白);处理2:CF(常规施肥,基肥为有机肥与化肥配施,追肥为化肥);处理3:40%ZF+60%HF(40%沼液+60%化肥);处理4:60%ZF+40%HF(60%沼液+40%化肥);处理5:80%ZF+20%HF(80%沼液+20%化肥);处理6:100%ZF(全沼液)。结果表明,施用沼液能提高土壤有机质含量,且提高幅度与沼液用量呈正相关关系。苗期CF处理土壤速效养分含量明显高于沼液处理,但至成熟期60%ZF+40%HF处理土壤速效养分含量最高。与CF相比,施用沼液提高土壤盐分含量和pH值,玉米成熟期40%ZF+60%HF、60%ZF+40%HF、80%ZF+20%HF、100%ZF处理的土壤盐分含量和pH值分别增加22.48%、47.50%、59.78%、71.25%和1.19%、2.25%、3.00%、3.84%。成熟期玉米秸秆养分含量、籽粒产量与品质均以60%ZF+40%HF处理最高,方差分析表明,该处理与80%ZF+20%HF处理产量无显著差异。综合分析认为,60%沼液与40%化肥配施适合玉米生长对养分的需求,产量最高,品质最优。

沼液与化肥不同比例配施对番茄产量和品质的影响

采用随机区组设计,共6个处理,分别为CK(空白对照)、CF(有机肥基施和化肥追施)、ZF 40%+HF 60%(40%沼液+60%化肥)、ZF 60%+HF 40%(60%沼液+40%化肥)、ZF 80%+HF 20%(80%沼液+20%化肥)、ZF 100%(纯沼液),研究了沼液与化肥不同比例配施对番茄产量和品质的影响。结果表明,沼液与化肥配施提高了番茄叶片叶绿素含量,其中以ZF 60%+HF 40%处理最高,且在番茄定植后的30、65和110 d分别比CF和ZF 100%处理提高了3.74%和7.52%、3.36%和21.38%、30.76%和37.22%。沼液与化肥配施提高了番茄果实中维生素C和可溶性糖含量,降低了可滴定酸含量,沼液施用量越多,对果实品质改善效果越明显。番茄产量以ZF 60%+HF 40%处理最高,分别是CK、CF、ZF 40%+HF 60%、ZF 80%+HF 20%、ZF处理的1.58倍、1.15倍、1.08倍、1.12倍和1.21倍。ZF80%+HF 20%和ZF100%处理果实中检测到铜、锌等重金属,所有处理均未检出抗生素。综合分析认为,ZF 60%+HF 40%处理能明显提高番茄产量和改善果实品质。

Entropies of the Y-Junction Type Nanostructures

Recent research on nanostructures has demonstrated their importance and application in a variety of fields.Nanostructures are used directly or indirectly in drug delivery systems,medicine and pharmaceuticals,biological sensors,photodetectors,transistors,optical and electronic devices,and so on.The discovery of carbon nanotubes with Y-shaped junctions is motivated by the development of future advanced electronic devices.Because of their interactionwithY-junctions,electronic switches,amplifiers,and three-terminal transistors are of particular interest.Entropy is a concept that determines the uncertainty of a system or network.Entropy concepts are also used in biology,chemistry,and applied mathematics.Based on the requirements,entropy in the form of a graph can be classified into several types.In 1955,graph-based entropy was introduced.One of the types of entropy is edgeweighted entropy.We examined the abstract form of Y-shaped junctions in this study.Some edge-weight-based entropy formulas for the generic view of Y-shaped junctions were created,and some edge-weighted and topological index-based concepts for Y-shaped junctions were discussed in the present paper.

Metric Basis of Four-Dimensional Klein Bottle

The Metric of a graph plays an essential role in the arrangement of different dimensional structures and finding their basis in various terms.The metric dimension of a graph is the selection of the minimum possible number of vertices so that each vertex of the graph is distinctively defined by its vector of distances to the set of selected vertices.This set of selected vertices is known as the metric basis of a graph.In applied mathematics or computer science,the topic of metric basis is considered as locating number or locating set,and it has applications in robot navigation and finding a beacon set of a computer network.Due to the vast applications of this concept in computer science,optimization problems,and also in chemistry enormous research has been conducted.To extend this research to a four-dimensional structure,we studied the metric basis of the Klein bottle and proved that the Klein bottle has a constant metric dimension for the variation of all its parameters.Although the metric basis is variying in 3 and 4 values when the values of its parameter change,it remains constant and unchanged concerning its order or number of vertices.The methodology of determining the metric basis or locating set is based on the distances of a graph.Therefore,we proved the main theorems in distance forms.

Algebraic Properties for Molecular Structure of Magnesium Iodide

As an inorganic chemical,magnesium iodide has a significant crystalline structure.It is a complex and multifunctional substance that has the potential to be used in a wide range of medical advancements.Molecular graph theory,on the other hand,provides a sufficient and cost-effective method of investigating chemical structures and networks.M-polynomial is a relatively new method for studying chemical networks and structures in molecular graph theory.It displays numerical descriptors in algebraic form and highlights molecular features in the form of a polynomial function.We present a polynomials display of magnesium iodide structure and calculate several M-polynomials in this paper,particularly the M-polynomials of the augmented Zagreb index,inverse sum index,hyper Zagreb index and for the symmetric division index.

Degree-Based Entropy Descriptors of Graphenylene Using Topological Indices

Graph theory plays a significant role in the applications of chemistry,pharmacy,communication,maps,and aeronautical fields.The molecules of chemical compounds are modelled as a graph to study the properties of the compounds.The geometric structure of the compound relates to a few physical properties such as boiling point,enthalpy,π-electron energy,andmolecular weight.The article aims to determine the practical application of graph theory by solving one of the interdisciplinary problems describing the structures of benzenoid hydrocarbons and graphenylene.The topological index is an invariant of a molecular graph associated with the chemical structure,which shows the correlation of chemical structures using many physical,chemical properties and biological activities.This study aims to introduce some novel degree-based entropy descriptors such as ENTSO,ENTGH,ENTHG,ENTSS,ENTNSO,ENTNReZ1,ENTNReZ2 and ENTNSS using the respective topological indices.Also,the above-mentioned entropy measures and physico-chemical properties of benzenoid hydrocarbons are fitted using linear regression models and calculated for graphenylene structure.

不同温度对快速厌氧发酵物料滞留时间的影响

为了研究不同发酵温度对沼气产量以及沼液理化性质的影响,判断粪水厌氧发酵最短滞留期,以减少沼气工程投资成本,试验以猪粪水(TS=5%)为发酵原料,采用厌氧发酵方法,共设置3个处理组(发酵温度分别为15℃、25℃、35℃),检测了沼液的TS、有机质含量、pH值、甲烷含量以及甲烷累计产量等指标。结果表明:厌氧发酵分别进行到第4,8,10天后,处理组3、处理组2、处理组1沼液的TS浓度维持相对稳定状态。与处理组1相比,处理组2和处理组3沼液中有机质显著下降期缩短2天;与处理组3相比,处理组1和处理组2沼液的pH值下降幅度明显降低。处理组1和处理组2沼气中甲烷含量高峰期均出现在厌氧反应的第3天,而处理组3则出现在第6天。处理组1、处理组2、处理组3中的甲烷产量分别在粪水滞留的第6天、第3天、第2天达到了每个处理组甲烷总产量的70.9%、75.3%、61.4%。说明发酵温度为15,25,35℃时,粪水快速厌氧发酵最佳滞留期为6,3,2 d。

软体沼气工程聚乙烯土工膜技术性能与成本分析

该研究以软体沼气工程聚乙烯土工膜为研究对象,对其技术性能和产品成本进行比对分析,以期为软体沼气工程膜材料提供理论参考与建议。研究材料为工程上常用的1.0~2.0 mm厚度的普通高密度聚乙烯土工膜(GH-1)、环保用光面高密度聚乙烯土工膜(GH-2S)、环保用单/双糙面高密度聚乙烯土工膜(GH-2T)和低密度聚乙烯土工膜(GL-1)。研究结果表明,2.0 mm厚度的不同型号土工膜材料成本是1.0 mm厚度土工膜的1.6~2.0倍;膜拉伸屈服强度以GH-2T为最高,而膜拉伸断裂强度和平均抗穿刺强度则以GH-2S为最高;膜的厚度与膜的抗老化、抗紫外线及使用年限无显著相关性。综合分析认为,高密度聚乙烯土工膜GH-2S材料成本适中,在抗拉伸性能、抗穿刺强度、抗紫外线和抗老化能力及使用年限方面具有不同程度的优势,可为软体沼气工程首选膜材料。

Hash Table Assisted Efficient File Level De-Duplication Scheme in SD-IoV Assisted Sensing Devices

The Internet of Things(IoT)and cloud technologies have encouraged massive data storage at central repositories.Software-defined networks(SDN)support the processing of data and restrict the transmission of duplicate values.It is necessary to use a data de-duplication mechanism to reduce communication costs and storage overhead.Existing State of the art schemes suffer from computational overhead due to deterministic or random tree-based tags generation which further increases as the file size grows.This paper presents an efficient file-level de-duplication scheme(EFDS)where the cost of creating tags is reduced by employing a hash table with key-value pair for each block of the file.Further,an algorithm for hash table-based duplicate block identification and storage(HDBIS)is presented based on fingerprints that maintain a linked list of similar duplicate blocks on the same index.Hash tables normally have a consistent time complexity for lookup,generating,and deleting stored data regardless of the input size.The experiential results show that the proposed EFDS scheme performs better compared to its counterparts.

总固体浓度对猪粪水快速厌氧发酵的影响

为了探讨中温(30℃)条件下不同总固体(TS)浓度对猪粪水快速厌氧发酵的影响,以期获得猪粪水快速厌氧处理的最佳TS浓度和发酵时间,试验采用厌氧发酵方法共设3个TS浓度(4%,处理1;5%,处理2;6%,处理3)处理,发酵8 d,测定沼液TS浓度、pH值、产气量和全氮、全磷、全钾、甲烷含量。结果表明:在发酵的前4 d,处理1,2,3的产气量分别达到总产气量的87.5%、87.9%和83.3%,处理3的甲烷含量最高,但与处理2无显著差异(P>0.05);在发酵的前4 d,各处理沼液pH值下降幅度随粪水TS含量的增大而增大。在整个厌氧发酵期间,各处理粪水TS浓度的变化与有机质变化趋势相似,发酵对各处理沼液中的全氮、全磷、全钾含量无显著影响(P>0.05)。说明物料的TS浓度为5%时,发酵4 d适合猪粪水的快速厌氧发酵处理。

沼液与化肥配施对苹果生长及土壤理化性状的影响——以烟台红富士苹果为例

以10年生苹果树品种烟台红富士为试验试材,探讨苹果的生长情况、土壤理化性质同沼液化肥搭配施用比例的关系,期望为沼液作肥料进行利用提供科学依据。各组所施肥料含氮量相等,设置7种处理:处理1,CK(空白);处理2,CF(基肥为牛粪有机肥,追肥为化肥);处理3,40%ZF+60%HF(40%沼液+60%化肥);处理4,60%ZF+40%HF(60%沼液+40%化肥);处理5,80%ZF+20%HF(80%沼液+20%化肥);处理6,100%ZF(全沼液);处理7,100%HF(全化肥)。结果表明,施用沼液能使土壤有机质含量、盐分含量和pH值提高。与100%HF处理比较,搭配施用的沼液与化肥在果树花期能够使土壤速效养分含量降低,至果实成熟期又升高,其中以40%ZF+60%HF处理最高。沼液与化肥配施不仅能提高苹果产量,而且能增加果实中糖度、维生素C含量和硬度,降低果实的酸度。综合果实品质和产量而言,40%ZF+60%HF处理最好,但与60%ZF+40%HF处理无显著差异。80%ZF+20%HF处理与100%ZF处理果实中检出Cu和Zn的残留,抗生素均未检出。综合统计分析认为,40%ZF+60%HF配施较适合苹果的生长。

不同厌氧反应器及沼液贮存设施成本和效益分析

为了对不同种类厌氧反应器和沼液贮存池的成本及经济效益进行分析,以筛选适合不同养殖规模的粪便厌氧处理设施,试验以1000 m^3为权衡规模,以全黑膜、钢筋混凝土、搪瓷钢板罐为原料的三种厌氧反应器以及全黑膜和钢筋混凝土沼液贮存池为研究对象,从其建设成本、运行成本、设计使用年限及经济效益进行定量和定性分析。结果表明:全黑膜厌氧反应器的建设总成本最低,分别为钢筋混凝土厌氧反应器和搪瓷钢板罐厌氧反应器的18.7%、6.0%(P<0.01);运行总成本以钢筋混凝土厌氧反应器最高,分别比搪瓷钢板罐和全黑膜厌氧反应器增加了9.7%、125.5%(P<0.01);厌氧反应器的使用年限以全黑膜厌氧反应器最短,仅为钢筋混凝土和搪瓷钢板罐厌氧反应器的38.1%、28.7%(P<0.01);搪瓷钢板罐厌氧反应器年平均收入最高,分别为钢筋混凝土厌氧反应器和全黑膜厌氧反应器的1.16倍和1.38倍(P<0.01)。与钢筋混凝土沼液贮存池相比,全黑膜沼液贮存池建设成本、运行成本优势明显。综合分析认为,全黑膜厌氧反应器适合中小型规模畜禽养殖场,而搪瓷钢板罐厌氧反应器适合大型或超大型畜禽养殖场,全黑膜沼液贮存池是目前较为经济便利的沼液贮存方式。

Robust Cluster-Based Routing Protocol for IoT-Assisted Smart Devices in WSN

The Internet of Things(IoT)is gaining attention because of its broad applicability,especially by integrating smart devices for massive communication during sensing tasks.IoT-assisted Wireless Sensor Networks(WSN)are suitable for various applications like industrial monitoring,agriculture,and transportation.In this regard,routing is challenging to nd an efcient path using smart devices for transmitting the packets towards big data repositories while ensuring efcient energy utilization.This paper presents the Robust Cluster Based Routing Protocol(RCBRP)to identify the routing paths where less energy is consumed to enhances the network lifespan.The scheme is presented in six phases to explore ow and communication.We propose the two algorithms:(i)energy-efcient clustering and routing algorithm and (ii)distance and energy consumption calculation algorithm.The scheme consumes less energy and balances the load by clustering the smart devices.Our work is validated through extensive simulation using Matlab.Results elucidate the dominance of the proposed scheme is compared to counterparts in terms of energy consumption,the number of packets received at BS and the number of active and dead nodes.In the future,we shall consider edge computing to analyze the performance of robust clustering.

Vegetation-environment relationship in conifer dominating forests of the mountainous range of Indus Kohistan in northern Pakistan

Environmental variables play a crucial role in shaping vegetation structure,mainly in mountainous ecosystems.Different studies have attempted to identify the environment-vegetation relationship of Conifer Dominating Forests(CDF)worldwide.However,due to differences in local climate and soil composition,different environmental drivers can be found.By applying multivariate analysis techniques,this study investigated the vegetation-environment relationship of CDF of Indus Kohistan in northern Pakistan.Our results showed that CDF of Indus Kohistan are distributed in five distinct ecological groups,which are dominated by different trees and understory species.A total of 7 trees and 71 understory species were recorded from the sampling sites.Cedrus deodara was the leading species among four groups,having the highest importance value(IV),density and basal area.Group I was dominated by Pinus wallichiana with the second highest importance value,density and basal area.In addition,elevation,slope,maximum water holding capacity(MWHC),soil moisture(SM),total organic matter(TOM),sodium,phosphorus and nickel showed highly significant influence on composition and distribution pattern of Indus Kohistan vegetation.Therefore,this study shows a new evidence of vegetation-environment relationship,pointing out specific drivers of vegetation structure in CDF of Indus Kohistan region in northern Pakistan.

Spin-Split Joint Density of States in GdN

We present an investigation of the optical constants of the near stoichiometric GdN films. Transmission and reflection spectra are collected for the paramagnetic and the ferromagnetic GdN in the photon energy range of 0.5-5.5 eV. In the ferromagnetic phase, behaviors of minority and majority spin states are specifically focussed on, which indicate spin-split joint density of states. The results confirm the LSDA＋U estimates of energy gap associated with the majority-spins and also the magnitude of spin splitting.

Metric-Based Resolvability of Quartz Structure

Silica has three major varieties of crystalline. Quartz is the main andabundant ingredient in the crust of our earth. While other varieties are formedby the heating of quartz. Silica quartz is a rich chemical structure containingenormous properties. Any chemical network or structure can be transformedinto a graph, where atoms become vertices and the bonds are converted toedges, between vertices. This makes a complex network easy to visualize towork on it. There are many concepts to work on chemical structures in termsof graph theory but the resolvability parameters of a graph are quite advanceand applicable topic. Resolvability parameters of a graph is a way to getting agraph into unique form, like each vertex or edge has a unique identification bymeans of some selected vertices, which depends on the distance of vertices andits pattern in a particular graph. We have dealt some resolvability parametersof SiO2 quartz. We computed the resolving set for quartz structure and itsvariants, wherein we proved that all the variants of resolvability parameters ofquartz structures are constant and do not depend on the order of the graph.

Effect of corn pre-puffing on the efficiency of MgO-engineered biochar for phosphorus recovery from livestock wastewater:mechanistic investigations and cost benefit analyses

To improve the phosphorus(P)recovery efficiency from livestock wastewater,a novel MgO doped mildewed corn biochar with thermal pre-puffing treatment(Mg-PBC)and without pre-puffing(Mg-BC)was synthesized and tested.The thermal-puffing pretreatment improved the effectiveness of metal soaking and MgO dispersion.P recovery time with Mg-PBC(7 h)was significantly shorter than that with Mg-BC(12 h).Moreover,Mg-PBC showed significantly higher P recovery capacity(241 mg g^(−1))than Mg-BC(96.6 mg g^(−1)).P recovery capacity of the Mg-PBC fitted to the Thomas model was 90.7 mg g^(−1),which was 4 times higher than that of Mg-BC(22.9 mg g^(−1))under column test conditions.The mechanisms involved in P recovery included precipitation,surface complexation,and electrostatic interaction.After adsorption,both Mg-BC and Mg-PBC showed relatively low regeneration abilities.The P loaded Mg-BC(Mg-BC-P)and Mg-PBC(Mg-PBC-P),the later particularly,obviously increased the available P content and promoted plant growth.The release of P increased with time in the Mg-PBC-P treated soil,while it decreased with time in the P fertilizer treated soil.A cost-benefit analysis revealed that thermal-puffing pretreatment greatly increased the profit of MgO doped biochar from−0.66 to 5.90 US$kg^(−1).These findings highlight that biomass pre-puffing is a feasible treatment to produce MgO modified biochar and to recover P from livestock wastewater,and that the Mg-PBC-P can be used as a slow-release P fertilizer.

Soil inorganic carbon sequestration through alkalinity regeneration using biologically induced weathering of rock powder and biochar

Soil inorganic carbon(SIC)accounts for about half of the C reserves worldwide and is considered more stable than soil organic carbon(SOC).However,soil acidification,driven mainly by nitrogen(N)fertilization can accelerate SIC losses,possibly leading to complete loss under continuous and intensive N fertilization.Carbonate-free soils are less fertile,productive,and more prone to erosion.Therefore,minimizing carbonate losses is essential for soil health and climate change mitigation.Rock/mineral residues or powder have been suggested as a cheaper source of amendments to increase soil alkalinity.However,slow mineral dissolution limits its efficient utilization.Soil microorganisms play a vital role in the weathering of rocks and their inoculation with mineral residues can enhance dissolution rates.Biochar is an alternative material for soil amendments,in particular,bone biochar(BBC)contains higher Ca and Mg that can induce even higher alkalinity.This review covers i)the contribution and mechanism of rock residues in alkalinity generation,ii)the role of biochar or BBC to soil alkalinity,and iii)the role of microbial inoculation for accelerating alkalinity generation through enhanced mineral dissolution.We conclude that using rock residues/BBC combined with microbial agents could mitigate soil acidification and SIC losses and also improve agricultural circularity.

Acoustic Properties of Metal-Organic Frameworks

Metal-organic frameworks(MOFs)have attracted significant attention in the past two decades due to their diverse physical properties and associated functionalities.Although numerous advances have been made,the acoustic properties of MOFs have attracted very little attention.Here,we systematically investigate the acoustic velocities and impedances of 19 prototypical MOFs via first-principle calculations.Our results demonstrate that these MOFs exhibit a wider range of acoustic velocities,higher anisotropy,and lower acoustic impedances than their inorganic counterparts,which are ascribed to their structural diversity and anisotropy,as well as low densities.In addition,the piezoelectric properties,which are intimately related to the acoustic properties,were calculated for 3 MOFs via density functional perturbation theory,which reveals that MOFs can exhibit significant piezoelectricity due to the ionic contribution.Our work provides a comprehensive study of the fundamental acoustic properties of MOFs,which could stimulate further interest in this new exciting field.