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Sulfur-containing compounds have diverse biological functions and are crucial in crop protection chemistry. In this study, a series of novel 1-methyl-1H-pyrazol-5-amine derivatives incorporating disulfide moieties were synthesized and evaluated for their antimicrobial properties. In vitrobioassays demonstrated that compound 7fdisplayed potent antifungal activity against Valsa mali, with an EC50value of 0.64 mg/L, outperforming allicin (EC50= 26.0 mg/L) but lower than tebuconazole (EC50= 0.33 mg/L). In vivoexperiments confirmed that compound 7fcould effectively inhibit V. maliinfection on apples at a concentration of 100 mg/L, similar to the positive control tebuconazole. Mechanistic studies revealed that compound 7fcould induce hyphal shrinkage and collapse, trigger intracellular reactive oxygen species accumulation, modulate antioxidant enzyme activities, initiate lipid peroxidation, and ultimately cause irreversible oxidative damage to the cells of V. mali. Additionally, compound 7bexhibited notable antibacterial activity, particularly against Pseudomonas syringaepv. actinidiae, with a MIC90value of 1.56 mg/L, surpassing the positive controls allicin, bismerthiazol, and streptomycin sulfate. These findings suggest that 1-methyl-1H-pyrazol-5-amine derivatives containing disulfide moieties hold promise as potent candidates for the development of novel antimicrobial agents.

In an effort to promote the development of new fungicides, a series of 48 novel N-(1-methyl-4-thiocyanato-1H-pyrazol-5-yl)-benzamide derivatives A1–A36and B1–B12were designed and synthesized by incorporating a thiocyanato group into the pyrazole ring, and their fungicidal activities were evaluated against Sclerotinia sclerotiorum, Valsa mali, Botrytis cinerea, Rhizoctonia solani, and Phytophthora capsici. In the in vitroantifungal/antioomycete assay, many of the target compounds exhibited good broad-spectrum fungicidal activities. Among them, compound A36displayed the best antifungal activity against V. maliwith an EC50value of 0.37 mg/L, which was significantly higher than that of the positive controls fluxapyroxad(13.3 mg/L) and dimethomorph(10.3 mg/L). Meanwhile, compound B6exhibited the best antioomycete activity against P. capsiciwith an EC50value of 0.41 mg/L, which was higher than that of azoxystrobin(29.2 mg/L) but lower than that of dimethomorph(0.13 mg/L). Notably, compound A27displayed broad-spectrum inhibitory activities against V. mali, B. cinerea, R. solani, S. sclerotiorum, and P. capsiciwith respective EC50values of 0.71, 1.44, 1.78, 0.87, and 1.61 mg/L. The in vivoexperiments revealed that compounds A27and B6presented excellent protective and curative efficacies against P. capsici, similar to that of the positive control dimethomorph. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses showed that compound B6could change the mycelial morphology and severely damage the ultrastructure of P. capsici. The results of the in vitroSDH enzymatic inhibition experiments indicated that compounds A27and B6could effectively inhibit the activity of P. capsiciSDH (PcSDH). Furthermore, molecular docking analysis demonstrated significant hydrogen bonds and Pi–S bonding between the target compounds and the key amino acid residues of PcSDH, which could explain the probable mechanism of action. Collectively, these studies provide a valuable approach to expanding the fungicidal spectrum of pyrazol-5-yl-benzamide derivatives.

An efficient enantioselective reductive amination and amidation cascade reaction has been developed. Catalyzed by iridium or rhodium complexes and with the help of sets of additives, the coupling of simple alkyl diamines and α-ketoesters occurs smoothly to afford the chiral cyclic piperazinone products. For disubstituted and monosubstituted alkyl diamine substrates, the corresponding reactions proceed through distinctive types of intermediates and thus require different transition metals to achieve high enantioselectivity, namely, iridium for the former and rhodium for the latter. In this transformation, the applied highly modular phosphoramidite–phosphine hybrid ligands displayed preeminent versatility and tunability.

On the basis of the structure of nicotlactone A (L1), a series of novel α-methylene-γ-butyrolactone derivatives B1–B43were designed and synthesized by structure simplification and active fragment replacement strategies, and their antiviral and antifungal activities were evaluated. The bioassay studies indicated that many target compounds possessed good to excellent antiviral activity against tobacco mosaic virus (TMV) and some of these compounds exhibited specific antifungal activities against Valsa maliand Fusarium graminearum. Compound B32exhibited the best anti-TMV activity (inactivation effect, 88.9%; protection effect, 65.8%; curative effect, 52.8%) in vivoat 500 mg/L, which is significantly higher than that of commercial virucides ribavirin and ningnanmycin. The inhibition effect of compound B32was also visualized by the inoculation test using green fluorescent protein (GFP)-labeled TMV. The preliminary antiviral mechanism of compound B32was investigated. Transmission electron microscopy (TEM) showed that compound B32could destroy the integrity of virus particles. Then, molecular docking and isothermal titration calorimetry (ITC) analysis further demonstrated that compound B32exhibited a strong binding affinity to the TMV coat protein with a dissociation constant (Kd) of 3.06 μM, superior to ribavirin. Thus, we deduced that compound B32may interfere with the self-assembly of TMV particles by binding TMV coat protein (CP). In addition, compound B28showed good in vitroactivity against F. graminearumwith an inhibition rate of 90.9% at 50 mg/L, which was greater than that of fluxapyroxad (59.1%) but lower than that of the commercial fungicide carbendazim (96.8%). The present study provides support for the application of these α-methylene-γ-butyrolactone derivatives as novel antiviral and antifungal agents in crop protection.

This paper mainly studied the problem of energy conserving in wireless sensor networks for target tracking in defensing combats. Firstly, the structures of wireless sensor nodes and networks were illustrated; Secondly, the analysis of existing energy consuming in the sensing layer and its calculation method were provided to build the energy conserving objective function; What’s more, the other two indicators in target tracking, including target detection probability and tracking accuracy, were combined to be regarded as the constraints of the energy conserving objective function. Fourthly, the three energy conserving approaches, containing optimizing the management scheme, prolonging the time interval between two adjacent observations, and transmitting the observations selectively, were introduced; In addition, the improved lion algorithm combined with the Logistic chaos sequence was proposed to obtain sensor management schemes. Finally, simulations had been made to prove the effectiveness of the proposed methods and algorithm.

To promote the discovery and development of new fungicides, a series of novel pyrazol-5-yl-benzamide derivatives were designed, synthesized by hopping and inversion of amide groups of pyrazole-4-carboxamides, and evaluated for their antifungal activities. The bioassay data revealed that compound 5IIcexhibited an excellent in vitro activity against Sclerotinia sclerotiorumwith an EC50value of 0.20 mg/L, close to that of commercial fungicide Fluxapyroxad(EC50= 0.12 mg/L) and Boscalid(EC50= 0.11 mg/L). For Valsa mali, compound 5IIc(EC50= 3.68 mg/L) showed a significantly higher activity than Fluxapyroxad(EC50= 12.67 mg/L) and Boscalid(EC50= 14.83 mg/L). In addition, in vivo experiments proved that compound 5IIchas an excellent protective fungicidal activity with an inhibitory rate of 97.1% against S. sclerotiorumat 50 mg/L, while the positive control Fluxapyroxadshowed a 98.6% inhibitory effect. The molecular docking simulation revealed that compound 5IIcinteract with TRP173, SER39, and ARG43 of succinate dehydrogenase (SDH) through a hydrogen bond and p−π interaction, which could explain the probable mechanism of the action between compound 5IIcand target protein. Also, the SDH enzymatic inhibition assay was carried out to further validate its mode of action. These results demonstrate that compound 5IIccould be a promising fungicide candidate and provide a valuable reference for further investigation.

Nortriterpenoids isolated from Walsura cochinchinensishave attracted much attention from both synthetic and medicinal chemists, yet only recently have efficient synthetic approaches to any members appeared. Shown here is that the common intermediate with a 6/6/5/6-fused tetracyclic ring nucleus can be converted to walsucochin family members. The first total syntheses of (±)-walsucochin A, (±)-walsucochinoids C–F, and their analogues were achieved in this work.

Fungal infections could cause tremendous decreases in crop yield and quality. Natural products, including flavonoids and (iso)quinolines, have always been an important source for lead discovery in medicinal and agricultural chemistry. To promote the discovery and development of new fungicides, a series of 3-(iso)quinolinyl-4-chromenone derivatives was designed and synthesized by the active substructure splicing principle and evaluated for their antifungal activities. The lead optimization was guided by bioactivity. The bioassay data revealed that the 3-quinolinyl-4-chromenone 13showed significant in vitroactivities against S. sclerotiorum, V. mali, and B. cinereawith EC50values of 3.65, 2.61, and 2.32 mg/L, respectively. The 3-isoquinolinyl-4-chromenone 25exhibited excellent in vitroactivity against S. sclerotiorumwith an EC50value of 1.94 mg/L, close to that of commercial fungicide chlorothalonil (EC50= 1.57 mg/L) but lower than that of boscalid (EC50= 0.67 mg/L). For V. maliand B. cinerea, 3-isoquinolinyl-4-chromenone 25(EC50= 1.56, 1.54 mg/L) showed significantly higher activities than chlorothalonil (EC50= 11.24, 2.92 mg/L). In addition, in vivo experiments proved that compounds 13and 25have excellent protective fungicidal activities with inhibitory rates of 88.24 and 94.12%, respectively, against B. cinereaat 50 mg/L, while the positive controls chlorothalonil and boscalid showed inhibitory rates of 76.47 and 97.06%, respectively. Physiological and biochemical studies showed that the primary action of mechanism of compounds 13and 25on S. sclerotiorumand B. cinereamay involve changing mycelial morphology and increasing cell membrane permeability. In addition, compound 13may also affect the respiratory metabolism of B. cinerea.This study revealed that compounds 13and 25could be promising candidates for the development of novel fungicides in crop protection.

Total syntheses of (±)-walsucochin B and (±)-walsucochinoids M and N have been achieved from farnesyl bromide. The key steps of the synthetic sequence are the titanocene-mediated radical cyclization and base-induced cycloaromatization for the rapid construction of the 6/6/5/6-fused tetracyclic skeleton. Importantly, a Cu-mediated remote C–H hydroxylation reaction has been developed to site-selectively install the oxygen function at the C-7 position of the target molecules, thus solving the biggest challenge for the synthesis of the compounds.

This paper is mainly on the problem of radiation interception risk control in sensor network for target tracking. Firstly, the sensor radiation interception risk is defined as the product of the interception probability and the cost caused by the interception. Secondly, the radiation interception probability model and cost model are established, based on which the calculation method of interception risk can be obtained. Thirdly, a sensor scheduling model of radiation risk control is established, taking the minimum interception risk as the objective function. Then the Hungarian algorithm is proposed to obtain sensor scheduling scheme. Finally, simulation experiments are mad to prove the effectiveness of the methods proposed in this paper, which shows that compared with the sensor radiation interception probability control method, the interception risk control method can keep the sensor scheduling scheme in low risk as well as protect sensors of importance in the sensor network.

In decades, the battlefield environment is becoming more and more complex with plenty of electronic equipments. Thus, in order to improve the survivability of radar sensors and satisfy the requirement of maneuvering target tracking with a low probability of intercept, a non-myopic scheduling is proposed to minimize the radiation cost with tracking accuracy constraint. At first, the scheduling problem is formulated as a partially observable Markov decision process (POMDP). Then the tracking accuracy and radiation cost over the future finite time horizon are predicted by the posterior carmér-rao lower bound (PCRLB) and the hidden Markov model filter, respectively. Finally, the proposed scheduling is implemented efficiently by utilizing the branch and bound (B&B) pruning algorithm. Simulation results show that the performance of maneuvering target tracking was improved by the improved interacting multiple model (IMM), and the scheduler time and maximum memory consumption were significant reduced by the present B&B pruning algorithm without losing the optimal solution.

To accelerate the development of novel fungicides, a variety of N-(pyrazol-5-yl)benzamide derivatives with a diphenylamine moiety were designed and synthesized using a pharmacophore recombination strategy based on the structure of pyrazol-5-yl-aminophenyl-benzamides. The bioassay results demonstrated that most of the target compounds had excellent in vitroantifungal activities against Sclerotinia sclerotiorum, Valsa mali, and Botrytis cinerea. In particular, compound 5IIIhexhibited remarkable activity against S. sclerotiorum(EC50= 0.37 mg/L), which was similar to that of fluxapyroxad (EC50= 0.27 mg/L). In addition, compound 5IIIc(EC50= 1.32 mg/L) was observed to be more effective against V. malithan fluxapyroxad (EC50= 12.8 mg/L) and comparable to trifloxystrobin (EC50= 1.62 mg/L). Furthermore, compound 5IIIhdemonstrated remarkable in vivoprotective antifungal properties against S. sclerotiorum, with an inhibition rate of 96.8% at 100 mg/L, which was close to that of fluxapyroxad (99.6%). Compounds 5IIIc(66.7%) and 5IIIh(62.9%) exhibited good in vivoantifungal effects against V. maliat 100 mg/L, which were superior to that of fluxapyroxad (11.1%) but lower than that of trifloxystrobin (88.9%). The succinate dehydrogenase (SDH) enzymatic inhibition assay was conducted to confirm the mechanism of action. Molecular docking analysis further revealed that compound 5IIIhhas significant hydrogen-bonding, π–π, and p−π conjugation interactions with ARG 43, SER 39, TRP 173, and TYR 58 in the binding site of SDH, and the binding mode was similar to that of the commercial fungicide fluxapyroxad. All of the results suggest that compound 5IIIhcould be a potential SDH inhibitor, offering a valuable reference for future studies.

Natural products are a valuable resource for the discovery of novel crop protection agents. A series of γ-butyrolactone derivatives, derived from the simplification of podophyllotoxin’s structure, were synthesized and assessed for their efficacy against tobacco mosaic virus (TMV). Several derivatives exhibited notable antiviral properties, with compound 3gdemonstrating the most potent in vivoanti-TMV activity. At 500 μg/mL, compound 3gachieved an inactivation effect of 87.8%, a protective effect of 71.7%, and a curative effect of 67.7%, surpassing the effectiveness of the commercial plant virucides ningnanmycinand ribavirin. Notably, the syn-diastereomer (syn-3g) exhibited superior antiviral activity compared to the anti-diastereomer (anti-3g). Mechanistic studies revealed that syn-3gcould bind to the TMV coat protein and interfere with the self-assembly process of TMV particles. These findings indicate that compound 3g, with its simple chemical structure, could be a potential candidate for the development of novel antiviral agents for crop protection.

The diphenyl ether molecular pharmacophore has played a significant role in the development of fungicidal compounds. In this study, a variety of pyrazol-5-yl-phenoxybenzamide derivatives were synthesized and evaluated for their potential to act as succinate dehydrogenase inhibitors (SDHIs). The bioassay results indicate certain compounds to display a remarkable and broad-spectrum in their antifungal activities. Notably, compound 12xexhibited significant in vitroactivities against Valsa mali, Gaeumannomyces graminis, and Botrytis cinerea, with EC50values of 0.52, 1.46, and 3.42 mg/L, respectively. These values were lower or comparable to those of Fluxapyroxad(EC50= 12.5, 1.93, and 8.33 mg/L, respectively). Additionally, compound 12xshowed promising antifungal activities against Sclerotinia sclerotiorum(EC50= 0.82 mg/L) and Rhizoctonia solani(EC50= 1.86 mg/L), albeit lower than Fluxapyroxad(EC50= 0.23 and 0.62 mg/L). Further in vivoexperiments demonstrated compound 12xto possess effective protective antifungal activities against V. maliand S. sclerotiorumat a concentration of 100 mg/L, with inhibition rates of 66.7 and 89.3%, respectively. In comparison, Fluxapyroxadshowed inhibition rates of 29.2 and 96.4% against V. maliand S. sclerotiorum, respectively. Molecular docking analysis revealed that compound 12xinteracts with SDH through hydrogen bonding, π-cation, and π–π interactions, providing insights into the probable mechanism of action. Furthermore, compound 12xexhibited greater binding energy and SDH enzyme inhibitory activity than Fluxapyroxad(ΔGcal = −46.8 kcal/mol, IC50= 1.22 mg/L, compared to ΔGcal = −41.1 kcal/mol, IC50= 8.32 mg/L). Collectively, our results suggest that compound 12xcould serve as a promising fungicidal lead compound for the development of more potent SDHIs for crop protection.

polycrystalline CuxYyOz are made through solid state reaction. Ferromagnetism is found in this YCuO system at room temperature. The ferromagnetism quite probably originates from Cu2Y2O5 , the Copper Yttrium Oxide. The average magnetic moment per Cu2+ is estimated to be 0.04μB. Itinerant electron magnetism is a rational explaination for the observed ferromagnetism. The experiment shows that the excessive amount of Cu may lead more defects and further distortion in the lattice and decrease the exchange interaction. This reminds us that the Copper Yttrium Oxide is a substance not only should be avoided in fabricating YBCO superconductors but also should be considered as a potential substance of magnetic semiconductor.

Natural products have been a valuable source of efficient and low-risk pesticides. In this work, a series of novel sesamolin derivatives A0–A31and B0–B4were designed and synthesized via structural simplification of furofuran lignan phrymarolin II, and their antiviral and antibacterial activities were systematically evaluated. The bioassay results showed that compound A24displayed remarkable inactivation activity against tobacco mosaic virus (TMV) with an EC50value of 130.4 μg/mL, which was superior to that of commercial ningnanmycin(EC50= 202.0 μg/mL). The antiviral mode of action assays suggested that compound A24may obstruct self-assembly by binding to TMV coat protein (CP), thus resisting the TMV infection. In addition, compound A25possessed prominent antibacterial activities, especially against Ralstonia solanacearumwith an EC50value of 43.8 μg/mL, which is better than those of commercial bismerthiazoland thiodiazole copper. This research lays a solid foundation for the utilization of furofuran lignans in crop protection.

As a large number of the multimedia information emerges, the cross-media retrieval system becomes an important research focus. The cross-media retrieval system is based on the traditional content retrieval, extracting color, texture, and shape features vector of the images. A new method was carried out in this paper. Firstly, the uniform semantic representational framework was built to organize the different mode media heterogeneous characteristics. Secondly, the Ontology database representing each type of media concepts was set up. The Ontology database organizes the low level features of the multimedia objects to associate multimedia files in the semantic level. Thirdly, the cross-media retrieval algorithm based on ontology was introduced. The results of the experiment showed that this cross-media retrieval method based on the Ontology was more effective and accurate.

The surface defects is an important factor affecting the quality of hot-rolled round steel, so the recognition of surface defects plays a very important role in the daily usage of the hot-rolled round steel. This paper aims to bring forward an appropriate method to find out the surface defects of the hot-rolled round steel under the help of Matlab software. First of all, the image edge of the round steel was detected, and the image was segmented. Secondly, the segmented image may appear bended, so it would be straightened to make the surface defects recognition easy. The third step is to eliminate image noise. Finally the processed image was analyzed and the appropriate recognition method was figured out. The results show that the method proposed in this paper is effective and accurate.

According to the requirements and characteristics of Marine Power Station quasi-synchronizing operation, a new high-precision digital synchronoscope is designed. Proteus and Keil are used as experimental platform. The corresponding software programming and peripheral hardware circuit design are completed. Moreover, the implementation and analysis of the main technical aspects are given. Simulation results show that the new digital synchronoscope fully achieve the functions that display and detection of frequency difference and phase difference between generator voltage and grid voltage. Besides, the operation is reliable, the detection is precise and the cost is low.

By applying the technology of composite ecological floating bed, a research was conducted to compare the eutrophic pollutant removal effects in domestic sewage among different filler proportions under static conditions. The results of proportion comparison experiments showed that the proportion of Plant: Filler = 1:1 had the best effects on NH4 +-N with the average removal rates as 97.93%, while as Plants: Filler = 1:1/2 had the best effects on TN and TP with the average removal rates of 89.05% and 91.55% respectively.

In the present work, a novel compound purifying tank was adopted in the rural sanitary sewage treatment. The cultivation and acclimation of biological film could be completed in a short start-up by aerobic precoating. According to the running results,the average COD removal rate reached 59.62%,and the removal efficiency of TP was 33.4%.For the denitrogenation,the removal rates were not remarkable (21.7 to NH4+-N,21.9 to TN),but the large removal quantity of NH4+-N and TN were abtained as 8.58mg/L and 9.12mg/L,respectively. The study suggests that the compound purifying tank is a potential alternative for rural sanitary sewage treatment.

To avoid the explosion of thermal pipeline and control the flow, pressure and temperature of thermal pipeline, the wireless sensor network (WSN) nodes should be designed and arranged. A new information monitoring system is developed baded on ZigBee. Based on MPLAB® ICD 2, with three sensors, using low-power PIC18F4620 controller chip and CC2420 processor integrated ZigBee technology, the WSN nodes were designed. The data collected by sensors can be sent to management center by wireless network. Manager can control the thermal flow consulting by the message from sensors and find out thermal pipeline danger in time. The system realizes real-time monitoring on the thermal pipeline. The test result showes that the perfomance of the system is stable and can reach the design requirements.

With heat flux increasing and cooling space decreasing in microelectronic and chemical products, micro heat pipe has become an ideal heat dissipation device in high heat-flux products. Through the analysis of its working principle, the factors that affect its heat transfer limits and the patterns in which copper powders are arrayed in circular cavity, this paper first established a mathematical model for the crucial factors in affecting heat transfer limits in a circular micro heat pipe with a sintered wick, i.e. a theoretical model for capillary limit, and then verified its validity through experimental investigations. The study lays a powerful theoretical foundation for designing and manufacturing circular micro heat pipes with sintered wicks.

A new dinuclear cobalt(II) complex [Co2L2Cl2(CH3OH)2] (1), where HL = 3‐[(furan‐2‐ylmethylimino)methyl]‐2‐hydroxy‐5‐methylbenzaldehyde, derived from the in situcondensation of 2,6‐diformyl‐4‐methylphenol with furfurylamine, was prepared and structurally and magnetically characterized. Single crystal X‐ray structural determination reveals that the structure consists of centrosymmetric dinuclear units with each CoIIion in a slightly distorted octahedral environment. Lines’ model, which in principle can theoretically separate in spin‐only and orbital contribution, was used to fit the variable temperature susceptibility (2–300 K), suggesting an intramolecular antiferromagnetic interaction between the cobalt(II) ions.

A fusion of polygons: A unique Dy10cluster with four fused Dy3triangles has been synthesized by incorporating the polydentate Schiff base ligand H4L in two different binding modes in its mono‐ and di‐deprotonated state (see figure). This Dy10compound represents the largest lanthanide cluster based on the peculiar Dy3triangles, therefore opening a promising route toward the design of novel magnetic materials.

To develop novel succinate dehydrogenase inhibitors (SDHIs), two series of novel N-4-fluoro-pyrazol-5-yl-benzamide and N-4-chloro-pyrazol-5-yl-benzamide derivatives were designed and synthesized, and their antifungal activities were evaluated against Valsa mali, Sclerotinia sclerotiorum, FusaHum graminearumSehw, Physalospora piricola, and Botrytis cinerea. The bioassay results showed that some of the target compounds exhibited good antifungal activities in vitroagainst V. maliand S. sclerotiorum. Remarkably, compound 9Ipdisplayed good in vitroactivity against V. maliwith an EC50value of 0.58 mg/L. This outcome was 21-fold greater than that of fluxapyroxad(12.45 mg/L) and close to that of the commercial fungicide tebuconazole(EC50= 0.36 mg/L). In addition, in vivo experiments proved that compound 9Iphas good protective fungicidal activity with an inhibitory rate of 93.2% against V. maliat 50 mg/L, which was equivalent to that of the positive control tebuconazole(95.5%). The results of molecular docking indicated that there were obvious hydrogen bonds and p−π interactions between compound 9Ipand succinate dehydrogenase (SDH), which could explain the probable action mechanism. In addition, the SDH enzymatic inhibition assay was carried out to further prove its mode of action. Our studies suggest that compound 9Ipcould be a fungicidal lead to discover more potent SDHIs for crop protection.