88 results about "Freshwater resources" patented technology

The present invention discloses a solar seawater desalinating greenhouse, comprising a main greenhouse, which is used for cultivating crops. A seawater distillation top level is added and arranged on the front part of the top of the greenhouse. An inner layer of the seawater distillation top level adopts a wavelength selective color plastic plate. The cover face of an outer lay of a roof adopts a translucent panel. A freshwater water collecting groove is arranged at the gutter in an inner layer of the roof. The freshwater collecting groove is communicated with a freshwater storage pool through a pipeline. A seawater storage pool, which is used for pumping and storing the seawater is connected and fixed on a jetting pipe in the inner layer of the roof through a water feeding column. Jetting holes are opened on the two sides of the jetting pipe. The present invention integrates the solar seawater desalinating device and the environmental controlled greenhouse in a whole, which is suitable for producing freshwater used in agriculture; in addition, the present invention also has the functions of sun shading and cooling, which can be used for desalinating the seawater and cultivating crops. The present invention can satisfy the need for vegetables supply and the drinking water for men and animals in coastal areas, islands, desert alkali region and so on where have seawater or brackish water but lack of freshwater resource.

The invention relates to a technique for the forestation of Chinese tamarisk on coastal tidal flats. According to the technical scheme of the invention, the technique comprises the following technological steps: (1) cultivating the shoot of Chinese tamarisk on plots with the salt content thereof being 0.3% to 0.6% by using the cutting propagation method; (2) transplanting the shoot of Chinese tamarisk to flowerpots or other containers to cultivate the container seedling of Chinese tamarisk, wherein the salt content of soil in the container is approximately 1.0% and no higher than 1.2%; (3) transplanting the ball-plant container seedling of Chinese tamarisk with the complete root system to the coastal tidal flats by proper density, wherein according to the conditions for selecting the coastal tidal flats, the coastal tidal flats can be immersed in seawater for a short time instead of immersed continuously for a plurality of days, and the salt content of the tidal flat soil is no higher than 3.0%. The invention has the following beneficial effects: by using the container seedling method, the invention guarantees the complete root system of Chinese tamarisk during the transplanting process, thereby avoiding the effect of root cutting and further increasing the survival rate of forestation of Chinese tamarisk under the condition that the salt content is high. Therefore, the technique is particularly suitable for the actual conditions in the area of coastal tidal flats short of freshwater resources.

The invention discloses a fecal sewage collection and treatment process and a device thereof. As the urbanization process of China is accelerated, the treating pressure of urban fecal sewage is greater. The fecal sewage collection and treatment process adopts two vacuum tanks to carry out the vacuum collection and the vacuum treatment of fecal sewage, the two vacuum tanks are not only vacuum collection tanks but also vacuum treatment tanks, and are mutually switched and respectively in the different working states, thereby leading the vacuum collection and the treatment to be continuous; the vacuum tank which is in the vacuum collection state continuously collects the fecal sewage and simultaneously recovers the condensation heat of the other vacuum tank when distilled water is generated by the vacuum treatment, thereby being used for the preheating and the pre-degasification of the fecal sewage, further saving energy, reducing operated process time and lowering operation cost; the distilled water is treated by a physical absorbent and then used for flushing a toilet, cleaning and the vacuum tanks, thereby achieving the self-sufficiency, having no need of an external water source for supplement and saving the freshwater resources.

The invention relates to a method for management of muddy coastal mudflat by echelon plantation of suaeda salsa, alfalfa and maize. The method includes: establishing a level-2 water draining and salt leaching system in a muddy coastal mudflat region; establishing a salt leaching and soil fertility improving plow layer; establishing a rainwater and freshwater resource utilization combined echelon propelled biological improvement mode. According to a plant-soil adaptability principle, echelon plantation of suaeda salsa, alfalfa and maize is carried out to realize echelon degradation of coastal saline soil from coastal saline soil, severe salinized soil, moderate salinized soil to plow land, wherein the suaeda salsa is a pioneer halophilous plant, the alfalfa is a salt-tolerant soil improving plant, and the maize is a field crop. Problems of high cost of physical and chemical measures for management of saline-alkali soil and long time of biological measures are solved, organic combination of ecological restoration and agricultural production is realized, a win-win purpose of ecological benefits and economical benefits is achieved, and technical supports are provided for utilization of coastal mudflat farmland.

Rice is the main crop in china, and the rice growing is the first farming. However, with the water consumption accounting for a half of national freshwater resource, the rice is the first water consumer, and the water utilization ratio is low. The phenomenon is described as one kilo of grain requiring one ton of water. Since the 1970s, the rice growing has been a typical example of agricultural non-point source pollution because of high production pursuance, and luxurious and random application of fertilizers and pesticides. For the food and etiological security, the rice growing must be reformed. With the reform of rice growing technology as a target, an ''irrigation paddy 'wheat planting type' high rice production wet planting method'' is invented. The invention comprises: (1) a soil fertility biological repair technology which integrates the soil utilization with the maintenance of soil fertility, with the paddy fertilization and crop rotation as the basis, (2) a direct sowing technology with seeding keeping, weeding and falling prevention technology as the basis, and (3) a novel water-saving rice growing irrigating system, that is, seeding in the wet soil, cultivating the root in a dry tube, developing ear in the ditch water and preventing the weakness in the dry and the wet environment, with physiological water requirement of the rice as the basis. The invention has the specific effects of saving the cost by 10 percent, saving the water by 40 percent, and achieving the stable production of 500Kg/mu, and has other ecological benefits.

Traditional fermentation generally adopts a freshwater resource. The invention discloses a novel seawater fermentation strain generating a biosurfactant. Fermentation with natural seawater as fermentation water and waste edible grease as a single carbon source is carried out to produce the biosurfactant rhamnolipid. Seawater fermentation enterprises can be built in coastal regions lacking a freshwater resource and having bad water quality to solve the dependence of the traditional fermentation industry on the freshwater resource. The strain is separated and purified through sweater enrichment culture, hypersalemia flat primary screening, synthetic medium secondary screening and seawater shaking bottle fermentation verification, and is determined as Pseudomonas aeruginosa through physiologic biochemical experiments and molecular identification analysis, is preserved in China General Microbiological Culture Collection Center on April 25, 2014, and has a preservation number of CGMCC No.9091. The strain uses the advantages of the seawater fermentation, and the obtained crude product rhamnolipid can be used in regional market promotion, and has a potential application prospect in the fields of the agriculture, the petroleum chemical industry, environment treatment, soil restoration, the cosmetic industry, the pharmacy industry and the food industry.

The invention relates to a selective permeable reactive barrier technique for controlling seawater invasion, which is used for avoiding waste of precious freshwater resources due to union pumping prior to discharge of freshwater and sweater in artificial pumping. The technique includes: pumping wells (3) are built between a land (1) and a sea (2), walls and bottom plates of the pumping wells (3) are made of selective permeable reactive barriers (4), and the selective permeable reactive barriers (4) are composed of porous medium (6) and salt-sensitive material (7). In freshwater, the salt-sensitive material (7) absorbs water to swell to block pores of the porous medium (6), and freshwater (5) cannot permeate the selective permeable reactive barriers (4) to enter the pumping wells (3). In seawater, the salt-sensitive material (7) dehydrates to shrink to allow pores of the porous medium (6) to be open, and seawater (5) can permeate the selective permeable reactive barriers (4) to enter the pumping wells (3). The pumping wells built based on the selective permeable reactive barriers can be used for preventing seawater invasion and treating sweater invasion.

The invention discloses a method for storing and using underground fresh water in coral reef sand. It consists of multiple water collection wells and water supply systems buried in the fill soil around coral reefs. The water collection wells are round or square, with holes evenly arranged on the side walls, and a roof with drain holes on the top. The water collection wells are used to collect rainwater , transported to the required location through the water supply system. A composite geomembrane is laid underwater to isolate the external seawater. The sloped water collection road can collect rainwater into the water collection well, and the rainwater will diffuse to the surrounding of the water collection well through the holes on the side wall of the water collection well, gradually forming a fresh water area. The invention can not only solve the problem of drinking water on the islands adjacent to the coral reefs, but also does not occupy the production and living land of the islands. It combines the construction of water conservancy infrastructure with sand blowing and reclamation, and can maintain normal operation without consuming extra energy or manpower and material resources after completion. Compared with the existing fresh water resource supply mode, it has good economic effect.

The invention discloses an apparatus and a method for desalinating sea sands. The apparatus comprises a recycled water production system and a sea sand desalination system, the recycled water production system least comprises a reclaimed water pool, a reclaimed water purification and desalination system and a recycled water storage tank which are sequentially connected, and reclaimed water from the reclaimed water pool is treated by the reclaimed water purification desalination system and then is stored in the recycled water storage tank; and the sea sand desalination system least includes a sea sand inactivation membrane breaking system and an impurity removal vibrating screen device, a first-stage sand washer, a second-stage sand washer and a third-stage sand washer which are sequentially arranged, the first-stage sand washer is connected with the reclaimed water pool, and the second-stage sand washer and the third-stage sand washer are respectively connected with the reclaimed waterstorage tank. The sea sand desalination apparatus uses reclaimed water or desalinated seawater as raw materials to desalinate sea sands, so freshwater resources are saved, and the sea sand desalination cost is reduced.

The invention provides a multi-source multi-load coordinated scheduling method and system considering load response uncertainty, and belongs to the technical field of new energy power systems. According to the method and system, load response uncertainty is considered; as for sea water desalination loads, sea water desalination and source network load flexible interaction are combined, and therefore, the running cost of a sea water desalination unit is reduced, the yield of fresh water resources is increased to a certain extent, and certain help is provided for solving the problem of global water resource shortage. The invention also provides a multi-time-scale coordinated scheduling method comprising day-ahead scheduling and intra-day scheduling. With the system and method adopted, the influence of the decrease of prediction precision of wind power and load power with time scale on the reliability of the system is reduced; the economy of coastal area power grid operation is improved;the utilization rate of new energy is increased; collected unit operation data, alarm information, multi-time scale regulation and control information and the like are monitored in real time, and controllability is achieved.

The invention relates to a method for synthesizing betaine, which is characterized in that the method uses trimethylamine and chloroacetic magnesium at the molar ratio of 1.02-1.03:1 for amination and synthesis; the reaction temperature of synthesis is controlled between 40 and 60 DEGC; the optimum reaction temperature is controlled between 53 and 55 DEG C; a pH value is controlled to be between 8 and 9; synthesis time is between 2.5 and 5 hours; continuous feeding and continuous discharging are adopted; and the feeding and discharging of reaction are regulated and controlled by use of a pH meter. The method has the advantages of eliminating frequent operation for feeding, synthesis and discharging during batch production, as well as unsafe factors possibly caused by the frequent operation, increasing production yield, treating and recycling water after the concentration of betaine solution and reducing the waste of freshwater resources.

The invention provides a method for carrying out south-to-north water diversion along a coastline cofferdam. According to the method for carrying out the south-to-north water diversion along the coastline cofferdam, the cofferdam technique is adopted, water gates, cofferdams and the like are firstly constructed on the mouths of rivers, such as the Yangtze River, the Yellow river and the like, in the south to achieve the damming of fresh water resources; then new coast defense dam bodies are constructed along the banks of the Yellow sea and the Bohai sea, and then a huge water delivering channel is formed between old coast defense dam bodies and the new coast defense dam bodies; finally, cofferdam water storage is carried out at a proper position of the Bohai sea to form a huge reservoir lake. According to the method for carrying out the south-to-north water diversion along the coastline cofferdam, the coastlines of the main rivers, such as the Yangtze River, the Yellow river and the like, extend towards the north, a large number of fresh water resources are delivered to the north in the gravity flow state, and the problem of water shortage in the mid-east region in the north is solved thoroughly. The method for carrying out the south-to-north water diversion along the coastline cofferdam has the advantages that the water delivering capacity is high, the construction cycle is short, water can be supplied stably, and construction cost and operating cost are extremely low.

The invention discloses a system and method for efficiently improving coastal saline-alkali soil with recycled water resources. The system comprises a soil body and a water storage well. The soil bodycomprises saline-alkali soil to be improved, a water permeable membrane layer, a water storage layer, a waterproof layer and undisturbed soil sequentially arranged from top to bottom. A water intakepipe is arranged in the water storage well. A water suction pump is arranged at the water inlet of the water intake pipe that extends to the bottom of a water intake well, and the outlet end of the water intake pipe is horizontally arranged above the surface of the saline-alkali soil to be improved. A tee junction and a valve are arranged on the water intake pipe, with one end being connected to an irrigation apparatus and another end being connected to a removal pipeline. Water is poured onto the saline-alkali soil to be improved and flows into the water storage well after washing, and then water is pumped to wash the saline-alkali soil. Such a process is repeated to wash the saline-alkali soil to be improved for the purpose of desalinization. The system and method disclosed in the invention have the advantages of simple and convenient operations, realized recycling of water resources, efficient saline-alkali soil washing with various water resources in short cycle, achieved improvement of saline-alkali soil without accumulation of salt in the surface soil, saving of fresh water resources, and low improvement cost.

The invention discloses an intelligent mop washing device. The device comprises a tank body, wherein a first water storage tank is arranged on the upper part of the tank body; a discharge pipeline communicated with a water pump working cavity is arranged on the lower side of the first water storage tank, and is provided with a first check valve; a second check valve is arranged on the bottom wallinside the water pump working cavity; a water inlet pipeline is arranged in the lower side of the second check valve; and a piston working cavity is formed in the inner wall on the right side of the water pump working cavity, and a piston is arranged in the piston working cavity. In the washing process, the device can be used for washing in multiple directions, so that the washing efficiency and washing quality can be greatly improved, and the treated sewage has higher quality after filtering for multiple times, adding a sewage treatment agent and stirring of a stirring arm in the process of treating sewage, and the sewage can be recycled after being pumped by the water pump, so that the freshwater resource can be greatly saved, and the waste of water resource can be reduced.

The invention relates to an explosion-proof and anti-collision device for an offshore freshwater resource database, which is designed for explosion protection of freshwater resource databases which float on the sea and similar offshore floaters, and belongs to the field of ocean engineering safety. The explosion-proof and anti-collision device for the offshore freshwater resource database comprises anti-collision baffles, anti-collision supporting plates and hinges, wherein the anti-collision baffles, the anti-collision supporting plates and the hinges are all installed at the periphery of a floater; one end of each anti-collision supporting plate is vertically hinged to the floater; the other end of each anti-collision supporting plate is vertically hinged to the corresponding anti-collision baffle; and the anti-collision baffles are arranged parallel to the floater and are densely arranged at the periphery of the floater. The explosion-proof and anti-collision device has the beneficial effects that the freshwater resource databases which float on the sea and the similar offshore floaters can be protected from being damaged when being impacted by external force, and the explosion-proof and anti-collision device can also have the protective effect although the freshwater resource databases which float on the sea and the similar offshore floaters are impacted by explosives such as torpedoes and the like.

The invention discloses an improving method for a saline-alkali land and belongs to the technical field of agriculture. For the saline-alkali land per mu, the method comprises the following steps: (1) uniformly spreading mushroom planting wastes on the surface of soil, after carrying out deep ploughing by using a deep ploughing machine, irrigating, and soaking the mushroom planting wastes for 10-15h; and (2) draining water in the saline-alkali land, carrying out rotary tillage, meanwhile, applying organic farm manure, an amino acid fertilizer and a composite microbial agent, and then, carrying out field planting on seedlings after 3 days since farmland fertility maintenance. The improving method for the saline-alkali land, disclosed by the invention, is used for improving the land under the condition of an original soil environment, wastes in the current mushroom planting process are adopted to form a breathable impermeable aggregate layer, saline and alkali are flushed to be clean by irrigation after the impermeable aggregate layer is mixed with a saline-alkali layer on a surface layer, and the impermeable aggregate layer can be used for effectively preventing planting oil on the surface layer from being salinized, so that a planting layer is suitable for plantation for a long term; and by using the method, flushing by using a great number of freshwater resources is not needed, so that the water consumption is effectively reduced.

The invention relates to an ecological restoration method for a resident-free island damaged bare land. The ecological restoration method comprises the steps of damaged bare land pretreatment, soil improvement, herbaceous plants spraying and sowing, trees and shrubs planting, water collection, fertilization and irrigation. According to the ecological restoration method, the island damaged bare land is pretreated, the terrain is prepared, and phytoremediation and catchment irrigation are facilitated; a planting soil foundation of the damaged bare land is improved through the soil improvement, and the soil improvement comprises planting soil replacement and matrix soil covering; a water collecting system is used for collecting rainwater and conveying the rainwater to an irrigation system, the problems of small island area and lack of fresh water resources are solved, and a water source is provided for the later growth period of plants; according to a slow-release fertilizer, a slow-release fertilizer pesticide bag is placed in a pesticide dispensing barrel, fertility is slowly released, the pesticide effect time is long, the water is supplied for fertilization through the irrigation system, a long-acting guarantee is provided for ecological restoration of the damaged bare land, the fertility and water storage capacity of soil of the damaged bare land are gradually restored, the biological diversity of an island is increased, and the stability and the stress resistance of a resident-free island ecological system are improved.

The invention relates to an antisludging agent special for a reverse osmosis membrane for seawater desalination. The lack of water resources is quite severe in China, especially in the northern coastal area, where fresh water resource shortage is critical, while seawater resources are rich; seawater desalination is one of efficient ways to solve the problem of fresh water resource shortage, and the most widely applied methods include the low-temperature multi-effect distillation method, the multistage flash distillation method, the reverse osmosis membrane method and the hot membrane coupling method which can all be used for large-scale production; due to the fact the saltness of seawater is quite high, scale formation is caused easily on the concentrated water side. The antisludging agent special for the reverse osmosis membrane for seawater desalination mainly contains phosphorus containing sulfo group copolymer, polyacrylic acid and organic phosphonic acid.

The invention discloses a coral island underground fresh water reservoir and a construction method thereof. The coral island underground fresh water reservoir comprises an annular vertical anti-seepage body and an underground storable reservoir basin defined by the annular vertical anti-seepage body, the annular vertical anti-seepage body is an underground cutoff wall or an anti-seepage curtain, is arranged along the outer edge of a coral island reef and is used for changing the seepage boundary of underground water, the purpose of expelling salt water and storing fresh water is achieved, thebasic function of storing the fresh water in the reservoir is achieved, and the underground reservoir basin is an underground loose coral gravel soil body defined by the annular vertical anti-seepagebody. According to the coral island underground fresh water reservoir and the construction method, the occurrence form of the underground fresh water of the coral island reef is changed, so that the small coral island reef which is not easy to form an underground fresh water lens body in a natural state can also form an underground fresh water resource; the underground fresh water is intercepted,the total amount of the underground fresh water resource is increased, the problems that under the natural state, the available fresh water amount of the coral island reef is small, and the fresh water lens body is unstable and fragile are effectively solved, and social and economic benefits are remarkable; and surface vegetation conservation is facilitated, and ecological benefits are remarkable.

The invention provides a drilling fluid prepared from oilfield produced water, and a preparation method thereof. The drilling fluid comprises water, a sulfur eliminator accounting for 0.1-0.3% of the mass of the water, a calcium and magnesium ion remover accounting for 0.1-0.3% of the mass of the water, a salt-resistant corrosion inhibitor accounting for 0.3-0.5% of the mass of the water, a tackifier accounting for 0.2-0.3% of the mass of the water, a flow pattern regulator accounting for 0.2-0.5% of the mass of the water, a flocculation coating agent accounting for 0.2-0.3% of the mass of the water, a fluid loss agent accounting for 0.8-1.1% of the mass of the water, an anti-sloughing agent accounting for 1-2% of the mass of the water, a liquid lubricant accounting for 2-5% of the mass of the water and a solid weighting agent accounting for 20-50% of the mass of the water. The drilling fluid prepared from oilfield produced water provides a new method for the treatment of oilfield water, and also has the advantages of reduction of the freshwater resource demand pressure of drilling fluids, reduction of the construction cost, increase of the economy benefits of oilfields, and realization of sustainable development of the oilfields.

The invention discloses a saline-alkaline land brackish water desalination treatment technology. The technology comprises the steps of water collection, sterilization, filtration, disinfection, desalination and distribution. The technology can directly treat the brackish water to form direct drinking water or irrigation water. The technology is mainly for meeting people's daily life drinking needs. The cooperation of a water intake controller, a flow sensor and an electromagnetic control valve makes converted freshwater used for crop drip irrigation when the drinking demand is low or zero, anddrip irrigation can ensure the normal growth of crops, and also can save water and prevent the waste of freshwater resources. The technology fully uses the underground brackish water in saline-alkaline regions to alleviate the shortage of the freshwater resources, and is especially for being applied to the saline-alkaline regions or regions rich in underground brackish water.

The invention discloses a method and device for preparing make-up water for power station boilers from municipal reclaimed water, which comprises the following steps of: (1) taking municipal reclaimed water, carrying out treatment on the municipal reclaimed water by using a biological aerated filter so as to obtain pretreated water; (2) carrying out treatment on the pretreated water by using an immersed ultra-filtrated water treatment device so as to obtain ultra-filtrated water; (3) carrying out treatment on the ultra-filtrated water by using a reverse osmotic water treatment device so as to obtain reverse osmotic water; and (4) carrying out treatment on the reverse osmotic water by using an EDI (electro-deionization) water treatment device so as to obtain the make-up water for power station boilers. In the invention, make-up water (with high requirements on water quality) for power station boilers is prepared through taking municipal reclaimed water as a water source, so that clean freshwater resources can be effectively saved, and the water pollution can be reduced, thereby realizing the benign circulation of water in the nature, so, the method and device disclosed by the invention are important measures for implementing sustainable development. The method disclosed by the invention is simple; the biological aerated filter is large in volume loading and hydraulic loading and short in hydraulic retention time; and the device is small in investment, low in energy consumption for running, and less in running cost.

The invention discloses an overwater protection device with wave dissipation and seawater desalting functions. The overwater protection device comprises upper and lower air chamber, a lower floating body, a turbine machine, a plant model, a vacuum pump, a filtering pipe, a unidirectional air feeding valve and a unidirectional intake and vent valve. When seawater passes through the device, the plant model is used for reducing wave energy through turbulent fluctuation in a flow direction and a vertical direction respectively, so as to realize the effect of wave dissipation and shore protection.A root, stem and leaf structure of the plant model can be used for generating inner crown laminar flow to promote the diffusion of nutrients of a water body and also can be used for enhancing the exchange of an offshore water body to ensure the stability of an offshore ecological system. Meanwhile, the device sufficiently utilizes an ocean wave resource; when waves are transmitted to the device, air pressure in the device is changed through wave surface floating and wave energy is used for replacing electric energy to provide power to a vacuum pump, so that the seawater desalting aim is realized. According to the overwater protection device, ecological shore protection engineering and a seawater desalting technology are combined, a freshwater resource lacking problem is solved and the stability of the offshore ecological system is ensured.

The invention discloses a sewage treatment method, comprising the following steps of: step 1, preparing an agent for performing sewage purification treatment according to the properties of sewage; step 2, pumping the agent to a reaction pool according to a dosage by using a metering pump while enabling sewage to flow in the reaction pool according to the flow of the sewage, and performing purification reaction on the agent and the sewage, and performing stirring, coagulating and precipitating to generate a supernatant and sludge; step 3, press-filtering the sludge via a press filter to obtain press filtrate and dry sludge, collecting the dry sludge and then treating the dry sludge separately; step 4, combining the supernatant with the press filtrate and pumping to a biochemical pool, performing biodegradation, and precipitating to obtain clarified solution and active sludge; and step 5, mechanically filtering the clarified solution obtained in the step 4, pumping the filtrate to a reservoir which is detected to be qualified, and conveying the filtrate in a water recycling system. The sewage treatment method disclosed by the invention is used for automatically performing purification treatment on enterprise sewage, and repeatedly using the reclaimed water, thus reducing the waste of freshwater resource and lowering enterprise production cost.

The invention discloses a sea surface crop planting device and a planting management system. The system comprises a planting groove, a first annular groove is formed in the outer circumferential sidewall of the planting groove, a plurality of first through holes are formed in the circumferential side wall of the planting groove, a plurality of opening holes are formed in the bottom of the annulargroove, and each of the opening holes is provided with a semi-transparent film; a plurality of connecting blocks are arranged on the end side of the planting groove, and limiting holes are formed inthe connecting blocks; the planting groove is communicated with the annular groove through the first through holes; a buoyance mechanism is fixed to the outer bottom of the planting groove; the buoyance mechanism comprises a first cylinder body and a second cylinder body, the first and second cylinder bodies slidably cooperate, an electric push rod is connected between the first cylinder body andthe second cylinder body, and a penetrating hole is formed in the first or second cylinder body. The sea surface crop planting device floats on the sea surface through the buoyance mechanism to achieve on-sea planting, planting irrigation is conducted after seawater is filtered by the semi-transparent films, freshwater resources are saved, and planting convenience is improved.