酿酒污水资源化应用性能及风险分析

酿酒污水因其有机物浓度高而难以高效处理,但城镇污水处理厂面临着因有机物不足而导致的低碳氮比(C/N)污水反硝化效果差的问题。因此,该实验考察了以酿酒污水作为碳源强化低C/N污水的亚硝酸盐氮(NO3--N)去除效果,对水力停留时间(HRT)进行了优化,并对关键微生物和技术风险进行了分析。结果表明,在HRT为12~36 h、酿酒污水和低C/N污水体积比500∶1、进水总氮(TN)19.7 mg/L的条件下,处理后化学需氧量(COD)、TN、NO3--N浓度可以满足污水处理厂尾水排放标准。HRT优化过程造成了菌群差异,其中食酸菌属(Acidovorax)是同步去除COD和NO3--N的主要异养反硝化菌属。此外,致病和移动元件表型富集表明,在HRT为12 h时微生物致病和传播综合风险最低。综上,酿酒污水的资源化利用技术是可行的,并且HRT为12 h是最高效、安全的技术参数。研究可为酿酒污水处理提供理论指导和参考。

State Space Models Based Efficient Long Documents Classification

Large language models like Generative Pretrained Transformer (GPT) have significantly advanced natural language processing (NLP) in recent times. They have excelled in tasks such as language translation question answering and text generation. However, their effectiveness is limited by the quadratic training complexity of Transformer models O (L2), which makes it challenging to handle complex tasks like classifying long documents. To overcome this challenge researchers have explored architectures and techniques such as sparse attention mechanisms, hierarchical processing and efficient attention modules. A recent innovation called Mamba based on a state space model approach offers inference speed and scalability in sequence length due to its unique selection mechanism. By incorporating this selection mechanism Mamba allows for context reasoning and targeted focus on particular inputs thereby reducing computational costs and enhancing performance. Despite its advantages, the application of Mamba in long document classification has not been thoroughly investigated. This study aims to fill this gap by developing a Mamba-based model, for long document classification and assessing its efficacy across four datasets;Hyperpartisan, 20 Newsgroups, EURLEX and CMU Book Summary. Our study reveals that the Mamba model surpasses NLP models such as BERT and Longformer showcasing exceptional performance and highlighting Mamba’s efficiency in handling lengthy document classification tasks. These results hold implications for NLP applications empowering advanced language models to address challenging tasks with extended sequences and enhanced effectiveness. This study opens doors for the exploration of Mamba’s abilities and its potential utilization, across diverse NLP domains.

Combined metabolic phenotypes and gene expression profiles revealed the formation of terpene and ester volatiles during white tea withering process

Withering is a critical process to form the unique aroma of high-quality white tea.To study the mechanism underlying aroma changes during the white withering,we herein conducted volatile metabolomics and transcriptomics of the young leaves from the'Fuding Dahaocha'tea cultivar.As the withering time extended,the content of major aroma components increased significantly,score of sensory evaluation and Owuor's flavor index(OFI)also increased.The aromatic substances that accumulated during white tea withering were mainly volatile terpenes and esters.Their change trends were largely consistent with the gene expression of theα-linolenic acid metabolic pathways,while the correlation between the trends in volatiles and the gene expression of the terpenoid biosynthesis pathways was more complex and induced by the jasmonic acid(JA)signaling pathway.Additionally,we also explored the regulation pattern of key genes in the signaling pathway by related transcription factors.Three coexpression networks strongly correlated to the variation of volatile component content during withering were identified by weighted gene coexpression network analysis(WGCNA).Our results provide a new perspective on the processing mechanism and quality improvement of white tea.

基于区块链和代理重加密的医疗物联网数据安全管理系统

目的:基于可扩展区块链网络和代理重加密机制,建立医疗IoT数据管理系统,以保障物联网(IoT)智能医疗系统的数据传输安全。方法:将物联网与区块链相结合,通过分布式架构提高远程监测数据的安全性和隐私性。在物联网设备的注册和验证阶段,采用零知识证明(ZKP)方法确保数据的完整性。将代理重加密技术与区块链相结合以存储哈希数据,确保系统的安全性,并通过智能合约的设计实现了访问控制。为实现区块链的可扩展性,使用基于星际文件系统(IPFS)的离线数据库来存储数据。此外,为提高数据存储效率,提出了改进工作量证明(PoW)共识机制。结果:所建立的系统可有效抵御各种类型的攻击。IoT节点数量为40个时,系统总注册时间小于100 s,不同事务数量下的区块创建和访问时间均小于200 s。当事务数量为25个时,所提改进PoW算法的交易挖掘时间为0.001 s,优于原PoW算法的0.0024 s。结论:基于区块链和代理重加密技术的数据管理系统,能够确保医疗数据的机密性、完整性和隐私性,且效率优于传统的区块链方法,有助于提高IoT背景下医疗数据的安全管理。

Patterns and drivers of plant sexual systems in the dry-hot valley region of southwestern China

Sexual systems play important roles in angiosperm evolution and exhibit substantial variations among different floras. Thus, studying their evolution in a whole flora is crucial for understanding the formation and maintenance of plant biodiversity and predicting its responses to environmental change. In this study, we determined the patterns of plant sexual systems and their associations with geographic elements and various life-history traits in dry-hot valley region of southwestern China, an extremely vulnerable ecosystem. Of the 3166 angiosperm species recorded in this area, 74.5% were hermaphroditic,13.5% were monoecious and 12% were dioecious, showing a high incidence of diclinous species. Diclinous species were strongly associated with tropical elements, whereas hermaphroditic species were strongly associated with temperate and cosmopolitan elements. We also found that hermaphroditism was strongly associated with showy floral displays, specialist entomophily, dry fruits and herbaceous plants.Dioecy was strongly associated with inconspicuous, pale-colored flowers, generalist entomophily, fleshy fruits, and woody plants, whereas monoecy was strongly associated with inconspicuous, pale-colored flowers, anemophily, dry fruits, and herbaceous plants. In addition, hermaphroditic species with generalist entomophily tended to flower in the dry season, whereas diclinous species with specialist entomophily tended to flower in the rainy season. However, independent of sexual systems, plants that produce dry fruits tended to flower in the rainy season and set fruits in the dry season, but the opposite pattern was found for fleshy fruit-producing plants. Our results suggest that in the dry-hot valleys, plant sexual systems are associated with geographic elements as well as various life-history traits that are sensitive to environmental change.

Progress and prospects of Mg-based amorphous alloys in azo dye wastewater treatment

Mg-based amorphous alloys exhibit efficient catalytic performance and excellent biocompatibility with a promising application probability,specifically in the field of azo dye wastewater degradation.However,the problems like difficulty in preparation and poor cycling stability need to be solved.At present,Mg-based amorphous alloys applied in wastewater degradation are available in powder and ribbon.The amorphous alloy powder fabricated by ball milling has a high specific surface area,and its reactivity is thousands of times better than that of gas atomized alloy powder.But the development is limited due to the high energy consumption,difficult and costly process of powder recycling.The single roller melt-spinning method is a new manufacturing process of amorphous alloy ribbon.Compared to amorphous powder,the specific surface area of amorphous ribbon is relatively lower,therefore,it is necessary to carry out surface modification to enhance it.Dealloying is a way that can form a pore structure on the surface of the amorphous alloys,increasing the specific surface area and providing more reactive sites,which all contribute to the catalytic performance.Exploring the optimal conditions for Mg-based amorphous alloys in wastewater degradation by adjusting amorphous alloy composition,choosing suitable method to preparation and surface modification,reducing cost,expanding the pH range will advance the steps to put Mg-based amorphous alloys in industrial environments into practice.

Influence of network structure on spreading dynamics via tie range

There are various phenomena of malicious information spreading in the real society, which cause many negative impacts on the society. In order to better control the spreading, it is crucial to reveal the influence of network structure on network spreading. Motifs, as fundamental structures within a network, play a significant role in spreading. Therefore, it is of interest to investigate the influence of the structural characteristics of basic network motifs on spreading dynamics.Considering the edges of the basic network motifs in an undirected network correspond to different tie ranges, two edge removal strategies are proposed, short ties priority removal strategy and long ties priority removal strategy. The tie range represents the second shortest path length between two connected nodes. The study focuses on analyzing how the proposed strategies impact network spreading and network structure, as well as examining the influence of network structure on network spreading. Our findings indicate that the long ties priority removal strategy is most effective in controlling network spreading, especially in terms of spread range and spread velocity. In terms of network structure, the clustering coefficient and the diameter of network also have an effect on the network spreading, and the triangular structure as an important motif structure effectively inhibits the spreading.

Low Gilbert damping in Bi/In-doped YIG thin films with giant Faraday effect

Magnetic films with low Gilbert damping are crucial for magnonic devices,which provide a promising platform forrealizing ultralow-energy devices.In this study,low Gilbert damping and coercive field were observed in Bi/In-dopedyttrium iron garnet(BiIn:YIG)thin films.The BiIn:YIG(444)films were deposited onto different substrates using pulsedlaser deposition.Low coercivity(<1 Oe)with saturation magnetization of 125.09 emu/cc was achieved along the in-planedirection of BiIn:YIG film.The values of Gilbert damping and inhomogeneous broadening of ferromagnetic resonance inBiIn:YIG films were obtained to be as low as 4.05×10^(-4)and 5.62 Oe,respectively.In addition to low damping,the giantFaraday rotation angles(up to 2.9×10^(4)deg/cm)were also observed in the BiIn:YIG film.By modifying the magneticstructure and coupling effect between Bi^(3+)and Fe^(3+)of Bi:YIG,doped In^(3+)plays a key role on variation of the magneticproperties.The low damping and giant Faraday effect made the BiIn:YIG film an appealing candidate for magnonic andmagneto-optical devices.

Relationship between intracranial pressure and neurocognitive function among older adults after radical resection of rectal cancer

BACKGROUND Older patients are prone to postoperative cognitive decline after laparoscopic rectal cancer surgery,which may be associated with increased intraoperative intracranial pressure(ICP).This study investigated the correlation between intra-operative ICP changes,as indicated by measurements of the optic nerve sheath diameter(ONSD)using ultrasonography,and subsequent cognitive function to provide better patient care.AIM To evaluate changes in ICP and associated postoperative neurocognition in older adults after laparoscopic radical resection for rectal cancer.METHODS We included 140 patients who visited the Mianyang Central Hospital for malig-nant rectal tumors,measured their ONSDs before surgery and 30 and 60 minutes after the Trendelenburg position during surgery,and evaluated the patients’cog-nitive function 1 day before surgery and 1,4,and 7 days after surgery.The Mini-Mental State Examination(MMSE)and confusion assessment method(CAM)scores of the patients with different ONSDs were compared at different times after surgery.RESULTS In patients with an ONSD greater than 5.00 mm(group A1),the MMSE scores at 1 day and 4 days after surgery were significantly lower than those of patients with an ONSD less than or equal to 4.00 mm(group A2)(P<0.05).The CAM scores of group A1 were significantly higher than those of group A2(P<0.05).The MMSE scores of group A1 on days 1 and 4 after surgery were significantly lower than those 1 day before and 7 days after surgery(P<0.05),while the CAM scores 1 day and 4 days after surgery were significantly higher than those 1 day before and 7 days after surgery.CONCLUSION Decline in cognitive function among older adults after the procedure may be related to intracranial hypertension during surgery.

2023年广东省中考23题第三问解法探究与启示

通过对2023年广东省中考23题第三问解法的探究得到启示:对数学概念的理解和掌握是解决问题的根基和关键;对“变与不变”的动态几何问题,应强化解题的途径和通性通法,淡化模型和技巧;构造(图)法是处理复杂几何问题的基本方法和常见策略,数学解题应从问题的结构和形式着手,倡导结构观下的数学解题.

Preparation, structure and properties of Mg/Al laminated metal composites fabricated by roll-bonding, a review

Laminated metal composites(LMCs) are a unique composite material and have great application prospects in automobiles, ships, aircraft,and other manufacturing industries. As lightweight materials, the Mg/Al LMCs are expected to combine the advantages of both Mg and Al alloys to broaden their application prospects. Roll-bonding is the most popular process for the fabrication of Mg/Al LMCs due to high production efficiency and good product quality stability. The roll-bonding process involves the deformation of the substrates and the formation of the interfacial diffusion layer. The latter will directly determine the interface bonding strength of Mg/Al LMCs. Bonding strength is very sensitive to the thickness of the reaction layer in the diffusion layer. When the thickness of the reaction layer exceeds 5 μm, the bonding strength decreases sharply. Therefore, controlling the thickness of the reaction layer is very important for the design of rolling parameters.The latest research also showed that the addition of intermediate layer metal and the construction of three-dimensional interfaces can further improve the interface bonding strength. How to apply these methods to roll-bonding is the focus of future research. Recently, a new rolling technique, corrugated roll/plat roll rolling+flat roll/flat roll rolling has been developed to fabricate Mg/Al LMCs. It can effectively promote the deformation of the hard layer and generate a wavy interface, resulting in the enhancement of the bonding quality and rolling quality.In the current review, the effects of rolling parameters and subsequent annealing on the interface structure of Mg/Al LMCs were elaborated in detail. The application of some special rolling techniques in the preparation of Mg/Al LMCs was also summarized. The latest research results on the relationship between interface structure and mechanical properties of Mg/Al LMCs were reviewed. Finally, further research directions in this field were proposed.

面向拔尖创新人才培养的仪器分析课程建设与改革实践

面向拔尖创新人才培养,针对仪器分析课程中存在的“知识杂、多、散,系统性不强;基本原理和仪器构造抽象复杂;学生解决实际问题能力不强”等教学痛点问题,结合数字资源和学习通等智慧教学工具,开展了“思政引领、资源保障、科教协同、多元融合”的教学改革实践。通过思政元素的无声渗透,科学发展史、经典科学前沿文献和重大科技事件创新过程的重现,虚拟仿真软件对基本原理的展示,以及教学手段的多元融合,全面深化学生对基本概念的理解,分析问题、解决问题能力的提升和科研创新能力的升华,培养其成为德才兼备的拔尖创新人才。

South Carolina forestland owners’ willingness to accept compensations for carbon sequestration

Background: Carbon sequestration through recommended forest management practices is an ecosystem service that helps mitigate climate change and its impacts while generating carbon credits for forestland owners to sell in cap-and-trade programs. The California’s cap-and-trade program (California’s carbon market hereafter) allows forestland owners from any part of the contiguous United States to supply carbon credits to compliance entities. In this study, we estimate South Carolina (SC) private forestland owners’willingness to accept compensations to participate in the California’s carbon market using a contingent valuation method. Results: We estimate forestland owners’mean willingness to accept as$67 per acre per year. Our results reveal higher probability of participation of forestland owners with interests in preserving forest ecosystems than those who do not. Additionally, forestland owners who trust in information about climate change from scientists or government are willing to participate more than those who do not. Conclusions: Various factors hinder landowners’ability to participate in carbon markets. Forestland owners in SC consider legislative uncertainty and long-time commitment as the main barriers to participation in California’s carbon market. From this research, average forestland tenure in SC is 27 years, which is far less than the 100-year time commitment of the California’s carbon market. Of those who agreed to participate, choosing between adopting and not adopting any of the three main forest management practices in the California’s carbon market:28% are likely to adopt improved forest management (IFM) practices, 24% are likely to adopt reforestation due to understocked forestlands, and 14% are likely to adopt avoided conversion. In another development, the concept of aggregation has dominated discussions in the California’s carbon market of late. It is an advocacy to include small-scale forestlands in the California’s carbon market. To aggregate, different forestland owners will combine their forestlands to participate. We find that 79% of SC forestland owners are willing to aggregate to participate. However, this research is unable to determine how much total forestland is available in SC for carbon market. We recommend future research in the State on forestland owners’participation in carbon market should consider evaluating forestland availability.

Photoinhibition of Leaves with Different Photosynthetic Carbon Assimilation Characteristics in Maize (<i>Zea mays</i>)

Strong light decreases the rate of photosynthesis and assimilates production of crop plants. Plants with different carbon reduction cycles respond differently to strong light stress. However, variation in photoinhibition in leaves with different photosynthetic characteristics in maize is not clear. In this experiment, we used the first leaves (with an incomplete C4 cycle) and fifth leaves (with a complete C4 cycle) of maize plants as well as the fifth leaves (C3 cycle) of tobacco plants as a reference to measure the photosynthetic rate (PN) and chlorophyll a parameters under strong light stress. During treatment, PN, the maximal fluorescence (Fm), the maximal quantum yield of PSII photochemistry (Fv/Fm), and the number of active photosystem II (PSII) reaction centers per excited cross-section (RC/CSm) declined dramatically in all three types of leaves but to different degrees. PN, Fm, Fv/Fm, and RC/CSm were less inhibited by strong light in C4 leaves. The results showed that maize C4 leaves with higher rates of photosynthesis are more tolerant to strong light stress than incomplete C4 leaves, and the carbon reduction cycle is more important to photoprotection in C4 leaves, while state transition is critical in incomplete C4 leaves.

Mg-Zn-Mn-Nd合金作为一次镁空气电池阳极的腐蚀和放电行为

利用金相显微镜、X射线衍射仪、带有能谱仪的扫描电镜、电化学测试及恒电流放电测试对挤压态及固溶时效态Mg-6Zn-Mn-x Nd(ZM61,x=0,0.2,0.6,0.8,1.0,质量分数,%)合金微观结构、耐腐蚀性能及放电性能进行表征。结果表明,Nd的微合金化能促进ZM61合金晶粒细化,挤压态及固溶时效态ZM61-0.6Nd合金在所有合金中具有最为优异的耐腐蚀性能及放电性能;然而,热处理却降低挤压态合金的综合性能。其中,挤压态ZM61-0.6Nd合金的腐蚀电流密度为1.611×10^(-5)A/cm^(2),在电流密度为1和10m A/cm^(2)放电24 h的放电电位分别为-1.517 V和-1.336 V(vs SCE),其阳极利用率约36%,在所有研究合金中具有最好的综合性能。分析认为,挤压态ZM61-0.6Nd合金良好的放电性能可归因于镁合金耐腐蚀性能的提升及放电产物的开裂效应。

The Impact of Human Activities on CO2 Intake by Carbonate Weathering: A Case Study of Conglin Karst Ridge-trough at Fuling Town, Chongqing, China

The chemical weathering can consume atmosphere/soil CO2. Human activities such as pollution, fertilization and acid precipitation have exerted a large impact on CO2 intake by carbonate weathering. Thus, based on the analysis on chemical component change of the karst groundwater in the karst ridge watershed of Conglin Village, Fuling District of Chongqing City, the influence of human activities such as fertilization, sewage discharges from mustard tuber processing, breeding industry and acid rain precipitation on carbonate weathering and CO2 intake in 1980, 2003 and 2006 was studied. The results showed that CO2 intake by carbonate rock declined with year. Because H+ derived from acid sewage discharge, fertilization and acid precipitation reacted with carbonate rock when mustard tuber production and swine breeding were developed fleetly after 2000 as well as the burning amount of high-sulfur coal augmented persistently, which led to the increase of(Ca2++Mg2+)/HCO3-. The difference on charge between Ca2++Mg2+ and HCO3- was balanced by NO3-+SO42-. The control on pollution and acid rain, especially the pre-neutralization of acid waste water, would rejuvenate the atmospheric CO2 intake strength of carbonate weathering besides the protection of water and soil environment.

Laser powder bed fusion additive manufacturing of NiTi shape memory alloys: a review

NiTi alloys have drawn significant attentions in biomedical and aerospace fields due to their unique shape memory effect(SME),superelasticity(SE),damping characteristics,high corrosion resistance,and good biocompatibility.Because of the unsatisfying processabilities and manufacturing requirements of complex NiTi components,additive manufacturing technology,especially laser powder bed fusion(LPBF),is appropriate for fabricating NiTi products.This paper comprehensively summarizes recent research on the NiTi alloys fabricated by LPBF,including printability,microstructural characteristics,phase transformation behaviors,lattice structures,and applications.Process parameters and microstructural features mainly influence the printability of LPBF-processed NiTi alloys.The phase transformation behaviors between austenite and martensite phases,phase transformation temperatures,and an overview of the influencing factors are summarized in this paper.This paper provides a comprehensive review of the mechanical properties with unique strain-stress responses,which comprise tensile mechanical properties,thermomechanical properties(e.g.critical stress to induce martensitic transformation,thermo-recoverable strain,and SE strain),damping properties and hardness.Moreover,several common structures(e.g.a negative Poisson’s ratio structure and a diamond-like structure)are considered,and the corresponding studies are summarized.It illustrates the various fields of application,including biological scaffolds,shock absorbers,and driving devices.In the end,the paper concludes with the main achievements from the recent studies and puts forward the limitations and development tendencies in the future.

Does pollinator dependence decrease along elevational gradients?

Plants have long been thought to be less dependent on pollinators for seed production at higher elevations due to adverse pollination environments.However,recent research has yet to consistently support the generality of this expectation.In this study,we asked whether pollinator dependence decreases along an elevational gradient and how it varies with various reproductive traits.To answer these questions,we quantified pollinator-plant associations and various reproductive traits for 112 flowering plants spanning a large elevational gradient(990-4260 m a.s.l.)in the Qinghai-Tibet Plateau.We found that flowering plants in the Qinghai-Tibet Plateau region are highly dependent on pollinators for seed production(76.2%of seed production was contributed by animal pollinators and 44.6%of plants would produce no seed without pollinator visitation).Contrary to our expectation,there was no significant elevational gradient in pollinator dependence index.Although the pollinator dependence index was not significantly correlated with pollen limitation,flower size,floral longevity,or reward type,it was correlated with compatibility status and flowering time.These findings indicate that pollinator dependence does not decrease along an elevational gradient in the Qinghai-Tibet Plateau.Our study also highlights the severe vulnerability of flowering plant seed production to pollinator declines under global change in the Qinghai-Tibet Plateau region,particularly for early-flowering or self-incompatible plants growing at higher elevations(e.g.,subnival belt).

Promoting hybrid twins structure to reduce yield asymmetry of rolled AZ31 plates by combining side-rolling and torsion

In this work,an as-rolled AZ31 square bar with c-axis//ND(normal direction)texture was used.Side-rolling and reciprocating torsion were performed to treat the bar.Microstructure evolution and tensile-compressive properties were investigated in detail.Initial rolled AZ31 bar exhibits a large yield asymmetry along the rolling direction(RD).Reciprocating torsion can generate extension twins to introduce twin boundaries and twin-texture.The twin structure can reduce yield asymmetry.However,only limited regions in the rolled AZ31 bar can be twinned during torsion.Pre-side-rolling along the transverse direction(TD)can generate two texture components(c-axis//TD texture and c-axis//ND texture)by introducing profuse{10–12}twins.Such dual texture components help increase the regions which are favorable for twinning during torsion.Finally,combining side-rolling and reciprocating torsion generates hybrid{10–12}twins structure on the entire cross-section,resulting in a remarkably low yield asymmetry.The relevant mechanisms were discussed in detail.

Magnetic field‐enhanced water splitting enabled by bifunctional molybdenum‐doped nickel sulfide on nickel foam

Herein,we report bifunctional molybdenum-doped nickel sulfide on nickel foam(Mo-NiS_(x)/NF)for magnetic field-enhanced overall water splitting under alkaline conditions.Proper doping of Mo can lead to optimization of the electronic structure of NiS_(x),which accelerates the dissociation of H2O and the adsorption of OH−in the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)processes,respectively.In addition,the magnetically active Mo-NiS_(x)/NF can further enhance the HER and OER activity under an applied magnetic field due to the magnetoresistance effect and the ferromagnetic(FM)exchange-field penetration effect.As a result,Mo-NiS_(x)/NF requires low overpotentials of 307 mV at 50mA cm^(−2)(for OER)and 136 mV at 10mA cm^(−2)(for HER)under a magnetic field of 10000 G.Furthermore,the electrolytic cell constructed by the bifunctional Mo-NiS_(x)/NFs as both the cathode and the anode shows a low cell voltage of 1.594 V at 10 mA cm^(−2)with optimal stability over 60 h under the magnetic field.Simultaneous enhancement of the HER and OER processes by an external magnetic field through rational design of electrocatalysts might be promising for overall water splitting applications.