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A mathematical model to describe the seismic vibrator and ground coupling is proposed based on dynamic analyses of the vibrator baseplate structure and properties of soil. This mathematical model is solved using Newmark’s method. It produces reasonable results and the trend of amplitude envelope follows the experimental data. With this model, characterization of the vibrator-ground coupling is performed. Modal analysis study shows that the motions between the vibrator reaction mass and baseplate experience a combination of a first-order vibration mode and a second-order vibration mode. The corresponding frequencies of two vibration modes are located at 2.77 Hz and 488.7 Hz, respectively. As the frequency goes up, the motion behavior of the reaction mass and baseplate is dominated by the second-order vibration mode. It is realized that the second-order vibration mode is responsible for the phase difference between the input sweep signal and the output force signal. Furthermore, the impact of the coupling system parameters on the vibrator output force is also investigated. It is observed that the vibrator output force decreases as the sweep frequency increases. The weight ratio of the reaction mass and the baseplate has an impact on the vibrator output force.

There are more than 900 million people in China's rural areas, and a great deal of waste is created in production and in living on a daily basis. The treatment and reverse re-using of agricultural waste is an important factor about the new green economy and safety of ecological environment in rural areas. China is the world's largest agricultural waste-producing country, so the analysis and research about the status and problems of rural waste facing China, and what countermeasures about developing the reverse logistics of agricultural waste can be obtained is very important to achieving sustainable agricultural development and constructing new rural areas into a well-off society.

Background The boundary of the target hepatic segment within the liver parenchyma cannot be marked by the use of a conventional anatomic hepatectomy approach. This study describes a novel methylene blue staining technique for guiding the anatomic resection of hepatocellular carcinoma (HCC). Methods Between February 2009 and February 2012, anatomic hepatectomy was performed in 106 patients with HCC via a novel, sustained methylene blue staining technique. Sustained staining was achieved by injecting methylene blue into the distal aspect of the portal vein after exposing Glisson's sheath. The hepatic pedicle was immediately ligated, and the hepatic parenchymal transection was performed along the interface between methylene blue stained tissue and unstained tissue. Results Anatomic hepatectomies included subsegmentectomy (n = 16), monosegmentectomy (n = 57), multisegmentectomy (n = 27), and hemihepatectomy (n = 6). The portal vein was injected successfully with methylene blue in 100% of cases, and complete staining of the target hepatic segment was achieved in 98 of 106 (92.5%) cases. Mean intraoperative bleeding was 360 ± 90 mL, and the postoperative complication rate was 24.5% (26/106). No perioperative mortality occurred. Operative margins were all negative on pathologic examination. Mean duration of postoperative follow-up was 40 months (range, 24-60). No local recurrence (around the operative margin) occurred. Conclusion This novel technique of achieving sustained staining by injecting methylene blue then immediately ligating the hepatic pedicle is simple and feasible. It can guide the selection of the operative margin during hepatic parenchyma transection to improve the accuracy of anatomic hepatectomy for the treatment of HCC.

Coal will remain the dominant source for electricity generation in the foreseeable future and power generation is the primary CO2 emission, so efficient and clean use of coal is the key to solve the low-carbon development. Carbon Capture and Storage (CCS) is the only currently available technology that can align increased use of fossil fuels with climate change goals. United Nations Intergovernmental Panel on Climate Change (IPCC) has take CCS as a necessary technology which is economical and can keep the greenhouse gases concentration in the atmosphere constant effectively. This paper explores the progresses achieved in CCS technology. The growth area and the challenges faced in CCS development and present stage's technical route were uncovered. It is of great strategic significance to research efficient and low consumption new CCS technology under Integrated Gasification Combined Cycle (IGCC) operating conditions, and develop the combination technical route of IGCC with CCS.

The great need for exploitation and application of natural gas over the long period of time boosts enormous demand for heating equipments. So it's extremely important to design and manufacture energy-saving and efficient natural gas heaters. Therefore, the present paper explores the structural characteristics of the widely used cylinder type natural gas heater. Theoretical and experimental investigations on the flow condition and temperature distribution of the intermediate heat-carrying medium in the cylinder were carried out. On the basis of this, a simple and effective improved structure of rotation type cylindrical natural gas heater is put forward so as to optimize the relative positions of fire tube, flue tube bundle and convective tube bundle, thus improving the thermal efficiency of natural gas heater and saving preliminary investment.

China's Energy Consumption is mainly based on coal in a long time and power generation is the primary CO2 emission; so efficient and clean use of coal is the key to solve the low-carbon development. Integrated Gasification Combined Cycle (IGCC) is an advanced clean coal power-generation system with the unique superiority of quasi-zero CO2 emission. Based on the description of current IGCC Benchmarking Demonstration Projects, the progresses achieved in the field of IGCC with Carbon Capture and Storage (CCS) technology were discussed; the growth area and the challenges faced in IGCC with CCS development and present stage's technical route were uncovered. It is of great strategic significance to research efficient and low consumption new CCS technology under IGCC operating conditions, and develop the combination technical route of IGCC with CCS.

In this article, a way of fault detection for solar array is proposed. Using microcomputer technique, the electric current and voltage signal of each series branch is collected by Hall sensor. The difference of maximum current value and other values is used as the basis for determine fault. Then calculate each branch's deviation, the faulty solar series branch can be identified. According to voltage signal, it can determine the fault section in the branch. At last, failure message will be produced for maintainer's prompt attention.