Rb-Sr Isotopic Geochronology and Geological Implications of Dongfeng Gold Deposit in Jiaodong Area

The superlarge Dongfeng gold deposit is located in the Potouqing faults-alteration belt of the eastern part of the ‘Zhao-Lai-gold ore belt’, which belongs to the northwestern part of the Jiaodong area. Tectonically, ore bodies are controlled by faults and gold mainly occurs in the pyrite and polymetallic sulfide-bearing quartz vein. In this paper, Rb–Sr isotopic analysis is carried out with the beresite, which formed by hydrothermal metasomatism, and the Rb–Sr isochron age is 125.5±6.7Ma, indicating this deposit set up in the early Cretaceous of the late Yanshanian. Based on the relationship between the Dongfeng gold deposit and the Mesozoic granite, it is suggested that the formation of the gold deposit is a complex geological process of gradual enrichment and precipitation of the ore-forming elements. The initial 87Sr/86Sr ratio of the beresite is 0.711502±0.000069, which indicates the ore-forming materials mainly come from the crust. Combined with the complex mineralization process of the Dongfeng gold deposit and the reported H-O isotopic data, it is suggested that the ore-forming materials are mainly derived from the crust with some mantle materials, while the ore-forming fluids are originated primarily from magmatic hydrothermal and mantle with some precipitate water

Pathogenic Factors and Immunological Treatment of Cervical Cancer

This paper attempts to analyze the related factors of cervical cancer combined with immunotherapy, taking cervical cancer patients as the experimental object, through the establishment of cervical cancer model, combined with natural immune agonists, immune activated monoclonal antibody and HPV polypeptide to explore its prevention or treatment of cervical cancer immune research.The results showed that the number of people with bad habits was more, and the incidence rate of cervical cancer was relatively high. However, for those without formal work, the number of cases of bad sexual behavior is more, and HPV transmission is easier, which also provides convenience for the occurrence of cervical cancer. The mechanism of action of tumor therapeutic vaccine is different from that of cytotoxic drugs. Its particularity lies in that the induction of specific anti-tumor immune response needs a certain period of time before it can be transformed into clinical effect; and patients with recurrence or metastasis usually receive multiple rounds of treatment, which may affect the immune system and reduce the efficacy of the vaccine

Anatomic Study of Endoscopic Transnasal Approach to Petrous Apex

With the development of Neurosurgery technology, there has been a qualitative leap forward with the appearance of microanatomy, which makes the deep brain tumors which were hard to be achieved in the past, and effectively reduces the mortality of patients. Petrous apex is a cone-shaped part of the anteromedial part of the temporal bone, which is deep. It has been a challenging area for surgical anatomy for a long time. In this paper, fresh adult perfused cadaveric head specimens and dry adult cadaveric head specimens were taken as the experimental objects. The anterior wall of sphenoid sinus and the internal septum of sphenoid sinus were excised under neuroendoscope. The structures of the lateral wall of sphenoid sinus were identified and dissected. The lateral wall of sphenoid sinus and the bone of skull base were opened with micro drill, The meninges were exposed and cut open, and the related structures were dissected, observed and photographed. The experimental results show that it is relatively safe to operate in the range of less than 8mm, and the rock tip can be found accurately. The measurement of the bony structure of the skull base is helpful for the surgeon to judge the course of the internal carotid artery and its adjacent structure

Dually Sulphophilic Chromium Boride Nanocatalyst Boosting Sulfur Conversion Kinetics Toward High‐Performance Lithium–Sulfur Batteries

Abstract The sluggish kinetics of sulfur conversions have long been hindering the implementation of fast and efficient sulfur electrochemistry in lithium–sulfur (Li–S) batteries. In this regard, herein the unique chromium boride (CrB) is developed via a well‐confined mild‐temperature thermal reaction to serve as an advanced sulfur electrocatalyst. Its interstitial‐alloy nature features excellent conductivity, while the nano‐lamination architecture affords abundant active sites for host‐guest interactions. More importantly, the CrB nanocatalyst demonstrates a dual sulphophilicity with simultaneous Cr─S and B─S bondage for establishing strong interactions with the intermediate polysulfides. As a result, significant stabilization and promotion of sulfur redox behavior can be achieved, enabling an excellent Li–S cell cyclability with a minimum capacity fading rate of 0.0176% per cycle over 2000 cycles and a favorable rate capability up to 7 C. Additionally, a high areal capacity of 5.2 mAh cm−2, and decent cycling and rate performances are still attainable under high sulfur loading and low electrolyte dosage. This work offers a facile approach and instructive insights into metal boride sulfur electrocatalyst, holding a good promise for pursuing high‐efficiency sulfur electrochemistry and high‐performance Li–S batteries

The Alteration Age of Fracture Zone and Its Implication for the Formation of Gold Deposits in Jiaodong Area

The gold deposits in Jiaodong are the mesothermal hydrothermal alteration vein deposits formed in Mesozoic tectono-magmatic activation area. The research about the isotope age of magmatic rocks and strata has fruitful achievements in Jiaodong region, but the research of the age of altered rock needs to be strengthened. Former researcher defined the gold deposits in Jiaodong area are crust source-deep melting-hydrothermal quartz vein-altered rock type gold deposit. The age of altered rock obtained by former researchers cannot give us an over view about regional metallogenic regularity. To find the method that using time of hydrothermal alteration to explain the regional metallogenic regularity, the author developed field research in the main mineralized alteration belts: (1) choose the beresitization and potassic altered rock belt which are widely distributed in fracture alteration zones in Jiaodong area to be the sample position, and they are easily to be contrasted; (2) these two kinds of altered rock have less affected by the brittle fracture, which means they have stable chemical components of alteration process; (3) the altered minerals in these two kinds of rock belts have ductile deformation with the same period of the alteration process, which can indicate the structural stress and strain status. The plagioclase and potassium feldspar particles in rock samples are the objectives of Potassium-argon dating (K-Ar dating) test. The test results show that the period of hydrothermal alteration was from 148.3±4.3 Ma to 52.03±0.70 Ma, which is the late Yanshanian of Early Cretaceous Epoch; and that the altered rock isotope age decreases gradually from west to east in Jiaodong region, which proves the occurrence time of hydrothermal alteration in west earlier than that in east. Through the research about the structure, the component of mineral hydrotherm, and the physical chemical parameters of mineralization, this paper analyzes the regional regularity and the epoch of ore formation. The conclusion indicates that the regulation of hydrothermal alteration and mineralization in Jiaodong area are controlled by the tectonic additional hydrostatic pressure, the temperature and pressure conditions of ore-forming fluid, and the distribution and change of ore-forming elements. The above-mentioned geological characteristics indicate that the gold deposits in Jiaodong region are of the compound tectonic hydrothermal deposit type

Rb-Sr Isotopic Geochronology and Geological Implications of Dongfeng Gold Deposit in Jiaodong Area

The superlarge Dongfeng gold deposit is located in the Potouqing faults-alteration belt of the eastern part of the ‘Zhao-Lai-gold ore belt’, which belongs to the northwestern part of the Jiaodong area. Tectonically, ore bodies are controlled by faults and gold mainly occurs in the pyrite and polymetallic sulfide-bearing quartz vein. In this paper, Rb–Sr isotopic analysis is carried out with the beresite, which formed by hydrothermal metasomatism, and the Rb–Sr isochron age is 125.5±6.7Ma, indicating this deposit set up in the early Cretaceous of the late Yanshanian. Based on the relationship between the Dongfeng gold deposit and the Mesozoic granite, it is suggested that the formation of the gold deposit is a complex geological process of gradual enrichment and precipitation of the ore-forming elements. The initial 87Sr/86Sr ratio of the beresite is 0.711502±0.000069, which indicates the ore-forming materials mainly come from the crust. Combined with the complex mineralization process of the Dongfeng gold deposit and the reported H-O isotopic data, it is suggested that the ore-forming materials are mainly derived from the crust with some mantle materials, while the ore-forming fluids are originated primarily from magmatic hydrothermal and mantle with some precipitate water