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With the continuous improvement of China’s current technology level, the Internet of Things (IoT) technology is also increasingly widely used in various fields. IoT is a network composed of electronic components, software, sensors, etc. With the development of IoT technology, users’ demand for remote control equipment is increasingly urgent. In this article, the genetic algorithm–backpropagation neural network (GA–BPNN) algorithm was deeply studied by combining genetic algorithm (GA) and backpropagation neural network (BPNN) algorithm, and its application in network security evaluation was discussed. This article mainly studied the security and remote control technology of computer network and applied it to intelligent agriculture. In the evaluation performance test of the GA–BPNN algorithm, the evaluation accuracy of GA, BPNN, and GA–BPNN under simple difficulty was 99.58, 99.15, and 99.92%, respectively, and the evaluation accuracy under difficulty was 96.72, 96.47, and 98.88%, respectively. This proved the effectiveness of the GA–BPNN algorithm. In addition, in the application of smart agriculture, through the experimental data and concentration change data, it can be seen that the use of air-driven CO2{\text{CO}}_{2} (carbon dioxide) for concentration replenishment can effectively adjust the requirements of crops on the concentration of CO2{\text{CO}}_{2}. Through the analysis of the system’s light compensation system, it was proved that the system has a good structure and remarkable light compensation effect; it can replenish light for crops in time, and the PLC control structure has good working performance. The correctness of the system design was proved.

The East Kunlun Orogen (EKO) is located in the western part of the Central Asian Orogenic Belt, and it records the Neoproterozoic-Early Devonian tectonic evolution involving the subduction and extinction of the Proto-Tethys Ocean. The Heihaibei granite is located in the South Kunlun belt within EKO. In this study, geochronology, geochemistry, and Hf isotope analysis of Heihaibei monzogranite and granodiorite were carried out. Their LA-ICP-MS zircon U-Pb results yielded ages of 414.1 [+ ou -] 2.0 and 417.8 [+ ou -] 2.0 Ma. The Heihaibei granite is peraluminous (A/CNK = 0.99-1.30), with high alkali contents (7.76-9.14 wt.%) and 10 000 Ga/Al (2.60-3.38), Fe[O.sup.T]/MgO (27.6-49.5), and Y/Nb ratios (1.93-2.93), suggesting that the Heihaibei granite is an [A.sub.2]-type granite. The Heihaibei granite samples have zircon [epsilon]Hf(t) values ranging from-6.3 to-0.3, which suggests that the Early Devonian granite was derived from partial melting of Mesoproterozoic ([T.sub.DM2] = 1797-1415 Ma) crust. When considering data on contemporaneous granites, geochronological and geochemical data for the Heihaibei granite indicate that it was emplaced in a post-collisional extension environment following the closure of the Proto-Tethys Ocean. The Heihaibei granite was formed by extension of the southern subduction accretionary complex as part of the post-collisional setting during the closure of the Proto-Tethys Ocean. Key words: Heihaibei granite, geochemistry, geochronology, zircon Hf isotope, [A.sub.2]-type granite, East Kunlun Orogen L'orogène du Kunlun oriental (OKO) est situé dans la partie occidentale de la ceinture orogénique d'Asie centrale et préserve un registre de l'évolution tectonique du Néoprotérozoïque au Dévonien précoce comprenant la subduction et la disparition de l'océan proto-Téthys. Le granite de Heihaibei est situé dans la ceinture du Kunlun méridionale, dans l'OKO. Une étude géochronologique, géochimique et des isotopes de Hf de monzogranite et de granodiorite de Heihaibei a été réalisée. La datation U-Pb sur zircons par LA-ICP-MS donne des âges de 414,1 [+ ou -] 2,0 Ma et 417,8 [+ ou -] 2,0 Ma. Le granite de Heihaibei est hypera-lumineux (A/CNK = 0,99-1,30), avec de fortes teneurs d'alcalis (7,76-9,14 % en poids) et des rapports 10 000 Ga/Al (2,60-3,38), Fe[O.sup.T]/MgO (27,6-49,5) et Y/Nb (1,93-2,93) élevés, ce qui indiquerait qu'il s'agit d'un granite de type [A.sub.2]. Les échantillons du granite de Heihaibei présentent des valeurs de [epsilon]Hf(t) sur zircons de-6,3 à-0,3 qui indiqueraient que le granite dévonien précoce est dérivé de la fusion partielle de croûte mésoprotérozoïque ([T.sub.DM2] = 1797-1415 Ma). Au vu de données sur des granites du même âge, les données géochronologiques et géochimiques pour le granite de Heihaibei indiquent qu'il a été mis en place dans un milieu d'extension post-collision suivant la fermeture de l'océan proto-Téthys. Le granite de Heihaibei s'est formé par l'extension du complexe accrétionnaire de subduction méridional au sein du milieu post-collision durant la fermeture de l'océan proto-Téthys. [Traduit par la Rédaction] Mots-clés: granite de Heihaibei, géochimie, géochronologie, isotopes de Hf de zircons, granite de type [A.sub.2], orogène du Kunlun oriental, 1. Introduction The East Kunlun Orogen (EKO) is the major component of the Central China Orogenic System and has a complex Precambrian to Cenozoic structural and magmatic history(Jiang et al. [...]

Aiming at the problems of pressure - bearing pipes thinning and even rupture caused by the high temperature corrosion of the biomass boiler superheaters, the microstructure and properties of superheater tube wall after service were analyzed based on working environment. Research results showed that elements such as Cl and alkali metals in the flue gas underwent a series of complex physical and chemical reactions with the heating surface in the form of gas, solid and liquid phases at high temperatures, resulting in the corrosion of the superheaters pipe wall. The fly ash was deposited on the metal surface and soakably adhered to the oxide layer, which made the oxide protective layer on the pipe wall surface fell off, leading to the thinning of the pipe wall. Meanwhile, the service temperature of the high temperature superheaters was higher than that of the medium temperature superheater, and the corrosive peeling of its oxide layer was more serious. After long - term service, the micro hardness and tensile property of the pipe wall of the high temperature superheater after corrosion was decreased, compared with that of the medium temperature superheater. But, both of them still met the standard requirements and service conditions. Therefore, taking appropriate protective measures was able to prevent further corrosion and thinning of the pipe wall, which could shorten the maintenance period and reduce operating costs.