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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 986-90, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-30048094

RESUMO

Some FeS2 samples among metamorphic belt between coal and intrusion from Wolonghu mine in the north of Anhui Province were retrieved to characterize the signature of Raman Spectral. The results show that, all Raman data of different samples can be divided into 3 types as Ⅰ, Ⅱ and Ⅲ according to distinct differences of in Raman mode (M), Raman shift (Δν) and scattering intensity (Ⅰ). There are five strong scattering modes including high value Eg (1.16~1.59×103), high value Ag (2.33~2.53×103) and low value Tg (0.20~0.27×103) in typeⅠand only former three modes in type Ⅱ although the value of Eg, Ag and Tg are similar between them. While there are only two modes of high value Eg about 327.6~328.8 cm-1 and low value Ag 389.0~390.1 cm-1. Our analyses indicate that type Ⅰ samples must be mixed crystal of pyrite and natural coke for the former three peaks are same to deformation and stretching vibration of Fe-[S2]2- and stretching vibration of S­S in pyrite, while the latter two are similar to the vibration of Tiny graphite crystals and stretching vibration of C­C among graphite crystal from Raman data. And typeⅡsample may be pyrite for typical pyrite Scattering peak and Type Ⅲ sample possibility are low-temperature crystalloblastic of pyrite for Marcasite spectrum features in Raman. Further analysis also showed that the formation pressure of typeⅠ and Ⅱ are the same while type Ⅲ samples formed in low pressure for Raman scattered intensity of typeⅠand Ⅱ are similar, and type Ⅲ samples is obviously lower than the former two. And the formation temperature of typeⅠ, typeⅡ and type Ⅲ significantly decreased in turn for Ag peak of them are turn to high frequency about 4.4~6.7, 4.5~8.4cm-1 respectively compared with the former. Thus,The authors' studies suggest that pyrite samples from Metamorphic coal and metamorphic zone in Wolonghu coal mine are products in high temperature, but samples from Magmatic rocks are Marcasite formed at low temperature.

2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(9): 2439-43, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25532341

RESUMO

Some FeS2 samples among Augen granite from Guanshanzhang mass in the west of Guangdong Province were retrieved to characterize the spectral signature of Raman. The results show that three distinct scattering modes active of Fe-[S2]2- Liberational Motion (Eg), Fe-[S2]2- Stretching Motion (Ag) and S--S Stretching Motion (Tg) are observed from all samples. Detailed analyses indicate that Raman shift (Δυ), Modes intensity (I) and full width at half maximum (FWHM) are different between each type pyrite. The spectra show that there are three peaks respectively about 318 cm(-1) (Δυ1), 381 cm(-1) (Δυ1) and 440 cm(-1) (Δυ1) in Banded pyrite and three peaks in others samples about 344 cm(-1) (Δυ1), 379 cm(-1) (Δυ1) and 430 cm(-1) (Δυ1). Under compression to Alterated pyrite, all modes (Eg, Ag and Tg) shift continuously to higher frequencies from Deformed samples to Euhedral type. Eg mode is much intenser than Ag mode as well as the latter is intenser than Tg mode too in Banded samples (I(Eg) >> I(Ag) >> I(Tg)), the intensity of Ag mode is higher than Eg mode, and the latter is much higher than Tg mode in other samples (I(Ag) > I(Eg) >> I(Tg)). Compared with Alterated pyrite, all modes of Eg, Ag and Tg intense continuously to higher frequencies from Euhedral samples to Deformed type. Those spectral characteristics above evidence that, the Raman shift and intensity of Banded samples is similar to marcasite, while those of others show characteristics of the pyrite. The crystallization temperature of Euhedral pyrite is higher than Deformed as well as Euhedral is higher than Alterated too. The formation pressure of Euhedral samples is higher than Alterated pyrite the same as Deformed pyrite hingher than Euhedral one too. Thus, The authors' studies suggest that the forming conditions of FeS2 in Guanshanzhang mass experienced marcasite period-->high-pressure pyrite period--> high-temperature pyrite period-->Alterated pyrite period.

3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(6): 1465-8, 2014 Jun.
Artigo em Zh | MEDLINE | ID: mdl-25358146

RESUMO

Some granite samples from Pozaiying molybdenite deposits in the west of Guangdong were retrieved to characterize the spectral signature of XRD, FT-NIR and Raman. The results show that compared to the Porphyry granite and granite in the far zone, the signal of XRD and Raman of granite in near zone is weaker while the signal of FT-NIR is stronger. The authors' analyses indicate that the FWHM of quartz (101) peak in XRD, Sericite peak (4 529 cm(-1)) in FT-NIR and quartz peak in Raman shift from the latter are higher than those of former two. Those spectral characteristics indicate that compared with other samples, the content of petrogenetic mineral in samples from near zone is lower while the content of alteration mineral is higher, and its crystallinity and crystallization temperatures are both lower. The authors' studies suggest that there may be an alteration zone, embracing the granite-porphyry, which comprised low temperature mineral, and the quartz-porphyry which related to molybdenite mineralization belongs to the zone near Guanshanzhang mass.

4.
Biochim Biophys Acta Rev Cancer ; 1878(5): 188958, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37495194

RESUMO

Pancreatic cancer (PC) is one of the most lethal malignancies, which is generally resistant to various treatments. Tumor angiogenesis is deemed to be a pivotal rate-determining step for tumor growth and metastasis. Therefore, anti-angiogenetic therapy is a rational strategy to treat various cancers. However, numerous clinical trials on anti-angiogenetic therapies for PC are overwhelmingly disappointing. The unique characteristics of tumor blood vessels in PC, which are desperately lacking and highly compressed by the dense desmoplastic stroma, are reconsidered to explore some optimized strategies. In this review, we mainly focus on its specific characteristics of tumor blood vessels, discuss the current dilemmas of anti-angiogenic therapy in PC and their underlying mechanisms. Furthermore, we point out the future directions, including remodeling the abnormal vasculature or even reshaping the whole tumor microenvironment in which they are embedded to improve tumor microcirculation, and then create therapeutic vulnerabilities to the current available therapeutic strategies.


Assuntos
Neovascularização Patológica , Neoplasias Pancreáticas , Humanos , Neovascularização Patológica/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Imunoterapia , Microambiente Tumoral , Neoplasias Pancreáticas
5.
Ying Yong Sheng Tai Xue Bao ; 25(5): 1319-26, 2014 May.
Artigo em Zh | MEDLINE | ID: mdl-25129931

RESUMO

To determine the mechanism of soil stabilizing through Bambusa oldhami root system, the vertical distribution of B. oldhami root system in soil was investigated, and the tensile strength of individual root and soil shear strength were measured in B. oldhami forest. The dry mass, length, surface area and volume of the B. oldhami root system decreased with the increasing soil depth, with more than 90% of the root system occurring in the 0-40 cm soil layer. The root class with D 1 mm occupied the highest percentage of the total in terms of root length, accounting for 79.6%, but the lowest percentage of the total in terms of root volume, accounting for 8.2%. The root class with D >2 mm was the opposite, and the root class with D= 1-2 mm stayed in between. The maximum tensile resistance of B. oldhami root, either with 12% moisture content or a saturated moisture content, increased with the increasing root diameter, while the tensile strength decreased with the increasing root diameter in accordance with power function. Tensile strength of the root, with either of the two moisture contents, was significantly different among the diameter classes, with the highest tensile strength occurring in the root with D < or = 1 mm and the lowest in the root with D > or = 2 mm. The tensile strength of root with 12% moisture content was significantly higher than that with the saturated moisture content, and less effect of moisture content on root tensile strength would occur in thicker roots. The shear strengths of B. oldhami forest soil and of bare soil both increased with the increasing soil depth. The shear strength of B. oldhami forest soil had a linear positive correlation with the root content in soil, and was significantly higher than that of bare soil. The shear strength increment in B. oldhami forest was positively correlated with the root content in soil according to an exponential function, but not related significantly with soil depth.


Assuntos
Bambusa/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Solo
6.
Ying Yong Sheng Tai Xue Bao ; 19(6): 1362-8, 2008 Jun.
Artigo em Zh | MEDLINE | ID: mdl-18808033

RESUMO

The samples of surface soil, deep soil, and vegetables were collected from the liver cancer's high- and low incidence areas in Zhujiang River Delta to study the relationships between soil Mn forms and vegetables' Mn enrichment. The results showed that the soil Mn in study area was mainly derived from parent materials, and rarely come from human activities. The average soil Mn content in liver cancer's high incidence area was 577.65 mg x kg(-1), being significantly lower than that of liver cancer's low incidence area (718.04 mg x kg(-1)) and whole country (710 mg x kg(-1)). The Mn forms in high incidence area were mainly of residual Mn and Fe-Mn oxide, and less of water soluble Mn and exchangeable Mn, with the sum of the latter two's distribution coefficients being not higher than 4%. In low incidence area, the distribution pattern of soil Mn forms was similar to that in high incidence area, but the absolute contents of the Mn forms were significantly higher. Soil total Mn and soil pH had significant effects on soil Mn forms. There existed significant positive correlations between soil total Mn and the Mn forms of Fe-Mn bound, humic acid bound, carbonate bound, and residual, and negative correlations between soil pH and soil water soluble and organic bound Mn forms. Among the test five kinds of vegetables, Youmai lettuce and Chinese cabbage in liver cancer' s high incidence area had a significantly lower Mn content than in low incidence area, while the other three had less difference. The Mn enrichment in test vegetables was positively correlated with to the content of soil available Mn (sum of water soluble Mn and exchangeable Mn), but had no correlations with the contents of soil total Mn and other Mn forms.


Assuntos
Neoplasias Hepáticas/epidemiologia , Manganês/análise , Solo/análise , Verduras/química , China/epidemiologia , Ecossistema , Monitoramento Ambiental , Monitoramento Epidemiológico , Humanos , Incidência , Medição de Risco
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