ABSTRACT
With the discovery of two-dimensional (2D) ferroelectric materials such as CuInP2S6andα-In2Se3, the ferroelectric field effect transistors (Fe-FETs) based on these materials have entered a rapid-development period. The metal/semiconductor contact is an unavoidable topic in the construction of devices. In this paper, heterostructuresα-In2Se3/metals (Pd, Pt, Cu, Ag and Au) are discussed. According to different stacking types, the structures and energy of 160 heterostructures are calculated and compared. Whenα-In2Se3contacts with the Pd, Pt and Cu, theα-In2Se3may transforms intoß-In2Se3. This phenomenon has hardly been mentioned or analyzed in previous reports. Contacting with the Au and Ag, theα-In2Se3maintains the original structure. The internal physical mechanism of phase transition is explained from the binding energy and the charge transfer. The paper provides sufficient theoretical support for research and development of the Fe-FETs based onα-In2Se3.
ABSTRACT
OBJECTIVE: To investigate the characters of Raman spectrum in gastric cancer patients through comparing serum of functional dyspepsia patients, serum of gastric cancer patients with SGC7901 cell culture fluid, correlation with culturing time of cell line, and research the recourse of these special Raman peak. METHODS: Peripheral blood samples were collected from 25 gastric cancer patients and 10 functional dyspepsia (FD) patients. Human gastric cancer cells of the line SGC7901 were cultured. The serum samples of the gastric cancer patients and of the FD patients, and the culture fluid of SGC7901 cell underwent Raman spectroscopy with 230 nm and 100 nm as the least peaks respectively. Serum of normal person, lysate, and 1604 culture fluid were used as controls. RESULT: Seven reproducible Raman peaks at the wavelengths of 583, 633, 656, 674, 707, 773 and 799 nm were detected, with 230 nm as the least peak, in the serum samples of gastric cancer patients. Raman peaks at the wavelengths of 633, 656, and 674 nm were detected only in the serum samples of gastric cancer patients, and the Raman peaks at the wavelengths of 533, 707, 773, and 799 nm of the serum of gastric cancer patients (96.5 +/- 6.0, 76.9 +/- 4.7, 63.7 +/- 4.5, 285.7 +/- 18.6) were all remarkably higher than those of the serum samples of FD patients (40.3 +/- 1.8, 27.9 +/- 1.9, 22.9 +/- 1.4, 113.2 +/- 7.7, all P < 0.01). Similar condition, with 100 nm as the least peak, could detected in the Ramon peaks at the above mentioned wavelengths between the serum samples of the gastric cancer patients and the 1640 culture medium. The Raman peak of the cell culture fluid was positively correlated with the time of cell culture. The Raman peaks of the gastric cell lysate at the wavelengths of 583, 633, and 656 nm were significantly different from those of the cell culture fluid (P = 0.027, 0.029, and 0.043 respectively). CONCLUSION: The serum of gastric cancer patients has specific reproducible Raman spectrum. The cell content possibly is part of the reason of the special characters in Raman spectrum of gastric cancer serum.
Subject(s)
Spectrum Analysis, Raman/methods , Stomach Neoplasms/blood , Adult , Aged , Cell Extracts/analysis , Cell Line, Tumor , Dyspepsia/blood , Female , Humans , Male , Middle Aged , Stomach Neoplasms/pathologyABSTRACT
The gastric cancer cell and normal cell were comparatively detected by means of laser Raman spectrum in the present paper. The special Raman spectrum wave crest of gastric cancer cell was inquired. It was found that the special Raman spectrum wave crest of gastric cancer cell differs from the one of normal cell. After the sample at concentration of 1.25 x 10(5) individual x mL(-1) was cultivated for several days, a few special Raman spectrum wave crests of sample at 583, 633 and 656 nm respectively were detected. This is a few new special Raman spectrum wave crests rarely reported. Whether at the special Raman spectrum wave crests or at the same several Raman spectrum wave crests 674, 707, 773 and 799 nm for both canner cell and normal cell, the Raman spectrum intensity increases with the cancer cell concentration. As a result, the laser Raman spectrum analyse is considered truly a kind of rapid and effectual method to check cancer cell.
