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Giant clam shell mining (GCSM), a unique phenomenon occurring at remote coral reefs in the southern South China Sea (SCS), forms striking scars on the reef flats and damages the reef flat substrate. Through image analyses at three times (2004.02.02, 2014.02.26, and 2019.04.10) and in situsurveys at Ximen Reef, a representative site that has experienced GCSM, we quantified the GCSM-generated substrate damage and the corresponding recovery. GCSM was estimated to have occurred sometime between 2012 and 2014, causing reduction in live coral subarea and formation of micro-relief as trenches and mounds. GCSM-generated damage was restricted to the reef flat. After GCSM, coral and algae subarea increased, and the trenches and mounds tended to be filled and eroded, representing a natural recovery of the substrate. The legal prohibition on human disturbances at the coral reefs contributed to substrate recovery at Ximen Reef. This case also implied that recovery of the other coral reefs that suffered from GCSM is possible.

To evaluate the clinical therapeutic effect on mammary hyperplasia of electroacupuncture (EA) combined with scraping therapy.

Photocatalytic decomposition of water to produce hydrogen H2is an ideal way to solve energy and environmental problems, and the development of highly efficient polyoxometalate catalysts for photocatalytic hydrogen production has attracted wide attention. Herein, two Cu-modified Strandberg-type organophosphomolybdates were successfully synthesized, [Cu(C8H7N3)(H2O)2]2[(C6H5PO3)2Mo5O15]·4H2O (1) and [Cu(phen)(H2O)][Cu(phen)(H2O)2][(C6H5PO3)2Mo5O15]·2H2O (2) ([(C6H5P)2Mo5O21]Cu2) (C8H7N3= 2-(1H-pyrazol-3-yl)pyridine, phen = 1,10-phenanthroline). Two Strandberg-type organophosphomolybdates can be used for visible-light-driven hydrogen production. Also, compound 2exhibits an H2production rate of 6399 μmol g–1h–1after 8 h light exposure in the presence of photosensitization agent [Ir(dtbbpy)(ppy)2][PF6] and TEOA. In addition, cyclic tests showed that compound 2could be recycled four times without a significant reduction in catalytic performance. This work offers fresh insight into the development of novel polyoxometalates for efficient hydrogen evolution.

This paper reviewed oil spill incidents in Zhejiang coastal waters and characteristics of these incidents were analysed from geographical and seasonal distributions. Both operational and accidental oil spill incidents were examined, and key factors on ship accidents were identified. It was found that traffic density may be an important contributor to the oil spill incidents as key majority of accidents happened in busy waterways of important ports, especially Ningbo-Zhoushan area. The most significant oil spill risks were associated with navigational hazards of collision and grounding. The findings could be very useful for developing oil spill risk control and pollutants recovery measures.

A pump-signal combiner with a new processing method is reported in this paper. The core deformation of the signal fiber can be avoided by this method, and an 8+1 to 1 pump-signal combiner with 100 μm core-signal fiber feed-through is fabricated. The pump and signal coupling efficiencies are 96.8% and 98.0%, respectively. Furthermore, this pump-signal combiner is applied to a CW large mode area fiber laser with a counter pump configuration. The output power of the laser is 87 W.

Based on the theory of multi-body system dynamics and simulation software ADAMS/Car, the whole vehicle model was established. Afterwards by means of pylon course slalom, the accuracy of modeling was tested. The analysis and evaluation were later made to draw a conclusion that the handling stability of model needed improved. So as to improve the handling stability, the index lateral acceleration, yaw rate, side slip angle were taken as target function while suspension stiffness parameters were designed variables. Optimization of vehicle handing stability was practiced by applying second-order Response Surface Methodology (RSM) model. The relationship could be obtained by least square method obviously. Moreover applying with linear interpolation the final objective function was decided. The minimum of final objective function was the optimal result. Simulation analysis was performed again for the whole vehicle model by parameters modification. Subsequently, the results showed that this method greatly improved handling stability.

Acoustic seabed sediment classification method is always important research contents in marine geology and marine acoustics because of its characters of low-cost and high efficiency. At present, there are mainly three types of acoustic seabed sediment classification methods:(1) the echo signal statistical characteristics classification; (2) image texture classification; (3) submarine acoustic parameter inversion method. The principles of anterior two classification methods are similar, which is based on statistics, unknown sediment type can be concluded according to the statistical characteristics of known sediment. There are many usable acoustic equipments and commercial classification software for the two kinds of methods. The third type method is based on suitable seabed sediment model. Seabed acoustic characteristic parameters are inversed and thus seabed sediment can be classified. At present, there are few usable acoustic equipment and commercial classification software for the third method, but it's more accurate than the anterior two classification methods.

Internal circulation cabinets equipped with granular activated carbon (GAC) for adsorbing volatile organic compounds (VOCs) are widely used to store bottles containing organic solvents in universities, colleges, and hospital laboratories throughout Taiwan. This work evaluates the VOC adsorption capacities of GAC using various adsorption times for gas stream mixtures of 100 ppm toluene and 100 ppm o-xylene. Additionally, needle trap sampling (NTS) technology was used to indicate the time for renewing the GAC to avoid VOC breakthrough from adsorbents. Experimental results demonstrate that the proposed models can linearly express toluene and o-xylene adsorption capacities as the natural logarithm of adsorption time (ln(t)) and can accurately simulate the equilibrium adsorption capacities (Qe, g VOCs/g GAC) for gaseous toluene and o-xylene. The NTS, packed with 60–80 mesh divinylbenzene (DVB) particles, was compared in terms of extraction efficiency by simultaneously using the 75-μm Carboxen/polydimethylsiloxane–solid-phase microextraction (Carboxen/PDMS-SPME) fiber for time-weighted average (TWA) sampling, and experimental results indicated that the packed DVB-NTS achieved higher toluene extraction rates. Additionally, the NTS installed in the outlet air stream for adsorbing toluene and o-xylene exhausted through GAC accurately indicated toluene and o-xylene breakthrough times of 4700–5000 min. The GAC-NTS operational instructions to indicate the replacing time of adsorbent in the internal circulation cabinets are also included in this paper.Implications:The needle trap sampler has been evaluated to be a reliable device for indicating breakthrough of volatile organic compounds (VOCs) from adsorbent, which is used for adsorbing VOC emissions in a chemical storage cabinet. Applying this advanced indication technology for indicating VOC breakthrough would substantially reduce indoor emissions of VOCs in laboratories.

The author analyzed the working environment of special hydraulic turbine for cooling tower basing on the difference between the special turbine for cooling tower and the conventional power turbine. The former works in series pressure system and the water head determined by the pipeline resistance and the property of circulating water pump of cooling tower. It is the key to transform the cooling tower system successfully and save energy to build up a series special theories which include the specific speed of turbine for cooling tower, the type of turbine, the parameters selection, the design of the flow passage and runner of turbine by effectively transforming the conventional power turbine theory to the special turbine of cooling tower.

So far, the research about sediment ablation characteristic of the Yellow River is very insufficiency. For preventing and alleviating sediment ablation of the Yellow River stations by more scientific methods, it is very necessary to research ablation characteristic of hydraulic turbine systematically. The ablation characteristic of hydraulic turbine has direct relation with sediment size distribution. By research ablation of hydraulic turbine material under different sediment size distributions, the common rules are summarized between material ablation and sediment size distribution, and the key data and critical parameters are found out, which provides evidence for sediment ablation defend of hydraulic turbine.

The author analyzed the working characteristics of special turbine for cooling tower basing on the difference between the special turbine and the conventional hydraulic turbine. This paper points out that the special turbine works in a pressure water system and has typical ultra-low specific speed characteristic. These characteristics determine the type and parameters selection of the special turbine. Based on the theory the author has designed some special turbines in many projects in China. The practical operation shows that the turbines have high energy conversion efficiency and are steady in operation, with fairly good matching of the fans.

The hybrid wind/PV pumped-storage power system is to solve the electro-problem of remote and undeveloped areas short of power. Aim to the special physical geography condition of some island, hybrid wind/PV pumped-storage power system is brought forward, which is based on traditional hybrid wind/PV power system, and which storages energy by using pumped-storage. The mathematical models of main components of the system are brought forward. The optimization method is by using improved heredity arithmetic. Aim to the island the system model is brought forward, and the optimization method is applied, which effectively uses wind and solar resource, advancing stability of system, and reducing investment and run/management of the system.

One characteristic of Chinese rivers is their high silt contents. The Yellow River is unique for its excessive suspended sediment of the world river. Its annual sediment discharge is 116 million tons and its average sediment concentration is about 37.5 kg/m. Hydropower stations on the Yellow River are all facing the erosion problems on hydraulic turbines. The main harms of hydraulic turbine erosion are as follows: shorten repair cycle time and increase repair workload, less efficient plant operation, high maintenance costs and high potential safety risks. For example, Sanmenxia Hydropower Station, which is in the midstream of the Yellow River, has multi-year average sediment concentration 37.5kg/m, the maximum sediment 91lkg/m. Its hydraulic turbine is Kaplan turbine. Because of high sediment content, its turbine erosion is very serious. After running 3630 hours, the most of the 3mm stainless steel plate welded in the back of blades has come off in 4# turbine. The gap size between the blades and the middle ring already was extended from 7～8mm to 20mm and the weight loss of the blades was 780kg. After running 7595 hours, the base material of the blade back was alveolate and the gap size was extended to 40～50mm. After 31000 hours, the triangle of the blade head has been rubbed off and the gap size was extended to 120mm. The turbine was almost scrapped. To reduce or eliminate the silt erosion, an effective way is to use surface coating to the through-flow parts of the hydraulic turbine.

Oxidation of guaiazulene (1) with peracetic acid in hexane at 25 °C afforded as high as an 80% yield of the title biguaiazulenedione (12), which upon heating at 60 °C under nitrogen gave the title 1-azulenone (13) quantitatively. Oxidation of 12and 13was studied under various conditions, and these compounds were shown to be highly important key intermediates for a large number of the complex products obtained by autoxidation of 1.

Abstract: The undulation pump is a small size continuous flow displacement type blood pump that has been developed for an artificial heart. Using undulation pumps. 2 types of implantable total artificial hearts (TAHs), the undulation pump TAH (UPTAH) type 1 (UPTAH 1) and UPTAH type 2 (UPTAH 2) were developed. Both UP‐TAHs were designed to be small enough to implant into the chest of a goat, the experimental animal. UPTAH 1 could be reduced in size to 75 mm in diameter and 78 mm in length. The weight was 520 g. UPTAH 2 could be reduced in size to 75 mm in diameter and 80 mm in length. The weight was 650 g. UPTAH 2 could be tested in an animal experiment using an adult female goat weighing 52.3 kg. The UPTAH 2 could be implanted successfully into the goat's chest with a good fit. The goat stood after the surgery and extubation and survived for 3 h and 40 min; thus, the potential of the UPTAH for a practical implantable TAH was demonstrated.

This article introduces the theory analysis and experimental study on the performance of special turbine in cooling tower. The author analyses the speed-flow characteristics of turbine-fan unit and the speed-flow characteristics of ultra-low specific speed turbine itself. At the same time the author points out the principles and methods to determine the best operating point of turbine-fan unit. So it is very important to determine whether the specific turbine is in the best condition.

In this paper, the instrument is designed by basing on principle of the measurement method of straightness error measurement of deep hole, the design technologies of A/D converters, automatic control and computer are used. The instrument can automatically acquire data, the process of acquire data is convenient, fast, safe and the data is reliable.

This article discussed the preserve effect of the WC-HVOF coating to hydraulic turbine based on the research of sand abrasion in hydropower stations on the upstream of Yellow River. At the same time the importance role of WC coat for Hydraulic turbine protection and the great economic benefits from reasonable utilization of WC-HVOF coating are also been discussed in this article, using Sanmenxia hydropower stations as an example. All these have important reference significance for the other similar stations to use WC-HVOF coating to protect the hydraulic turbines.