Detection equipment for environmental pollution abatement

Abstract

The invention relates to the field of building environment monitoring, and particularly discloses detection equipment for environmental pollution abatement. A drilling unit; the horizontal sliding unit drives the drilling unit to horizontally slide and lock; the vertical sliding unit drives the drilling unit to vertically slide and lock, and the horizontal sliding unit or the vertical sliding unit is mounted on the mounting frame; a suction pump; the plurality of sampling units are communicated with the suction pump, a switch valve is connected between the plurality of sampling units and the suction pump, and the plurality of sampling units can suck water samples at different depths. According to the scheme, water samples at different positions and different depths can be collected, marking detection can be conveniently carried out on the different water samples, the water samples at different layers can be collected in an omnibearing mode, the conditions of whether the water samples are polluted or not, the pollution depth, pollution reasons and the like can be known, the underground water condition can be effectively supervised for a longer time, and the water quality is improved. And the reason can be conveniently found in time.

Description

Technical Field

[0001] The invention relates to the technical field of building environment monitoring, and in particular to a detection device for environmental pollution control. Background Art

[0002] In modern society, with the rapid development of urbanization and industrialization, the impact of construction sites on the environment is becoming increasingly significant. Construction sites not only produce a large amount of exhaust gas and noise, but also a large amount of wastewater. If these wastewaters are not treated or treated improperly, they will cause serious pollution to the surrounding environment. Therefore, it is particularly important to detect and manage the environmental water at construction sites.

[0003] During construction, a large amount of land is excavated and the soil is exposed, which is easily affected by wind and rain and prone to soil erosion. The mud and sand washed down by rain will bring a large amount of soil and pollutants into the water body; at the same time, a large amount of water is often needed to clean equipment and materials on the construction site, and these wastewaters contain various chemicals and pollutants, such as organic solvents, heavy metals, etc.; a large amount of garbage and waste is generated on the construction site, such as mud, sand, bricks, etc. If these exposed soil, mud, chemicals, pollutants or garbage are not properly handled, they will accumulate on the construction site. After being washed by rainwater, if they are directly discharged into rivers or lakes, they will cause water pollution.

[0004] In existing construction, when monitoring the water quality of the construction environment, water accumulated on the surface of the construction site or water to be discharged in a centralized manner is generally tested, and water in the soil layer of the construction site is generally not tested, resulting in a lack of supervision of the groundwater. The pollution of this part of the water will also affect the safety of the groundwater and surrounding soil. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a detection device for environmental pollution control to solve the problem that the water in the soil layer of a construction site is generally not detected, resulting in a lack of supervision of the groundwater, and the pollution of this water quality will also affect the safety of the groundwater and the surrounding soil.

[0006] In order to achieve the above object, the basic scheme of the present invention is as follows: a detection device for environmental pollution control, comprising:

[0007] Mounting frame;

[0008] Drilling unit;

[0009] A horizontal sliding unit that drives the drilling unit to slide horizontally and lock;

[0010] A vertical sliding unit that drives the drilling unit to slide vertically and lock, a horizontal sliding unit or a vertical sliding unit is installed on the mounting frame;

[0011] Suction pump;

[0012] A plurality of sampling units are connected to the suction pump, a switch valve is connected between the plurality of sampling units and the suction pump, and the plurality of sampling units can absorb water samples at different depths.

[0013] The technical principle of the present invention is: the mounting frame can drive the horizontal sliding unit or the vertical sliding unit, and the horizontal sliding unit and the vertical sliding unit can drive the drilling unit to move horizontally and vertically, so that the drilling unit can be moved to the groundwater monitoring point and then drill holes at the corresponding position, so as to adaptively control the drilling position, drilling depth and number of holes, and then cooperate with the sampling unit and the suction pump to collect water samples at different positions and depths, so as to facilitate the marking and detection of different water samples, and can collect water samples at different levels in an all-round way to know whether it is polluted, the depth of pollution and the cause of pollution.

[0014] This will enable more effective long-term monitoring of groundwater conditions, facilitate timely cause detection, and timely treatment of chemical substances, pollutants or garbage. It will also facilitate improving the safety of groundwater and surrounding soil at construction sites and effectively protect the construction environment.

[0015] Further, the drilling unit comprises:

[0016] Drill pipe;

[0017] A first motor drives the drill rod to rotate, and the first motor is fixedly connected to the vertical sliding unit.

[0018] Through the above arrangement, the first motor can drive the drill rod to rotate stably, and under the control of the horizontal sliding unit and the vertical sliding unit, it can move horizontally as a whole. Then, the drill rod and the first motor can move downward as a whole to perform stable drilling processing, thereby achieving stable drilling processing and smooth positioning.

[0019] Furthermore, the vertical sliding unit comprises:

[0020] A horizontal sliding block, which is connected to the horizontal sliding unit and has a drill hole vertically arranged on the horizontal sliding block for the drill rod to pass through;

[0021] A lifting guide rod, the lifting guide rod is vertically fixedly installed on the horizontal sliding block;

[0022] A support rod is horizontally fixedly installed on the lower side of the first motor, and a guide slider which can slide vertically along the lifting guide rod is provided on one end of the support rod away from the first motor.

[0023] Through the above arrangement, the horizontal sliding block can provide stable support for the installation of the first motor, the support rod and the guide slider can cooperate with the lifting guide rod, the first motor is limited by the support rod, and the lifting guide rod can guide the lifting of the first motor and the drill rod, thereby realizing the stable lifting of the drill rod and the first motor as a whole. During this process, the dead weight of the first motor and the drill rod can also provide power for the lowering of the drill rod to drill, making drilling more labor-saving.

[0024] Further, the horizontal sliding unit comprises:

[0025] Ball screw, the ball screw is installed horizontally and rotatably between the mounting frames;

[0026] A nut matched with the ball screw, the nut being mounted on a horizontal sliding block;

[0027] A second motor driving the ball screw to rotate, the second motor being fixedly connected to the mounting frame;

[0028] The guide bar is arranged in parallel with the ball screw, and both ends of the guide bar are fixedly connected with the mounting frame. A sliding hole is penetrated on the horizontal sliding block, and the sliding hole of the horizontal sliding block is in sliding contact with the guide bar.

[0029] Through the above-mentioned setting, the ball screw can cooperate with the nut, guide rod and horizontal sliding block, so that the rotational force of the ball screw is converted into the power for the horizontal sliding block to move horizontally along the ball screw and the guide rod, thereby controlling the horizontal position of the vertical sliding unit, the drilling unit and the sampling unit. The guide rod can provide guidance and support for the horizontal movement of the horizontal sliding block.

[0030] Further, the sampling unit comprises:

[0031] Sampling bottles;

[0032] A first water pipe, one end of which is flexible and passes through the drill hole, and the other end of which is fixedly passed through the horizontal sliding block and can be communicated with the sampling bottle;

[0033] A second water pipe, one end of which passes through the horizontal sliding block and is connected to the sampling bottle, the other end of which is connected to the suction pump, and an end surface of the first water pipe located in the sampling bottle is lower than an end surface of the second water pipe located in the sampling bottle;

[0034] The switch valve is installed on one end of the first water pipe and the second water pipe close to the bottle mouth.

[0035] Through the above arrangement, when the suction pump is turned on and the switch valve on the corresponding sampling bottle is turned on, the negative pressure is transmitted to the sampling bottle through the second water pipe, and the negative pressure of the sampling bottle is transmitted to the first water pipe. The first water pipe sucks the water sample in the sampling hole, and the sucked water sample enters the sampling bottle through the first water pipe. Since the end face of the first water pipe at one end in the sampling bottle is lower than the end face of the second water pipe at one end in the sampling bottle, the liquid level of the water sample is maintained at the lower end face of the second water pipe. When the second water pipe is not immersed in the water sample, the corresponding switch valve is closed, and the suction pump can also be directly controlled to pause to stop sampling. The sampling is accurate, reliable and automated.

[0036] Furthermore, the cross-sections of the first water pipe and the second water pipe are semicircular, and the cross-sections of the first water pipe and the second water pipe can be assembled into a circle, and a single switch valve is installed on the first water pipe and the second water pipe of the same sampling unit.

[0037] Through the above arrangement, it is convenient to realize the control of connection or disconnection of the first water pipe and the second water pipe through a single switch valve. The connection or disconnection control of the first water pipe and the second water pipe is simple and efficient, and the integration between the entire switch valve and the first water pipe and the second water pipe is high.

[0038] Furthermore, the sampling bottle is threadedly connected to the outer walls of the first water pipe and the second water pipe.

[0039] Through the above arrangement, the sampling bottle can be closely matched with the outer wall of the first water pipe and the second water pipe which are assembled into a circle. The sampling bottle can be cleaned and then screwed and installed on the first water pipe and the second water pipe. The first water pipe and the second water pipe and the sampling bottle are closely matched and easy to assemble and disassemble. It is easy to carry out multiple and long-term water sampling and processing at the monitoring point, and can accurately judge the groundwater quality in the construction environment.

[0040] Furthermore, the suction pump is a double-suction pump.

[0041] Through the above arrangement, when the water quality in the construction environment is treated, some of the reagents for treatment can be loaded into the sampling bottle, and the suction pump is controlled to reversely suck and open, so that the reagents can be transferred to the sampling bottle by air pressure through the second water pipe, and the reagents in the sampling bottle can flow back to the sampling holes through the first water pipe, thereby realizing the addition of diffusion reagents at the sampling holes of this layer, realizing the treatment of this part of the water environment, and effectively improving the treatment efficiency and accuracy.

[0042] Furthermore, a control unit is included, and the control unit includes:

[0043] PLC controller;

[0044] a first controller for controlling the first motor;

[0045] a second controller for controlling a second electric motor;

[0046] A second lead screw matched with the guide slider is arranged inside the lifting guide rod;

[0047] a third controller for controlling the guide slider to slide along the second lead screw;

[0048] a fourth controller for controlling the suction pump to be turned on or off;

[0049] The switch valves are all electronic switch valves, and the first controller, the second controller, the third controller, the fourth controller and the electronic switch valves are all connected to the PLC controller by electrical signals.

[0050] Through the above settings, the operation program and control duration can be input into the PLC controller according to the steps of horizontal sliding, vertical sliding, drilling, suction, sampling, etc., and then through the automatic control operation structure of the first controller, the second controller, the third controller, the fourth controller and the switch valve, a more automated drilling sampling process can be performed, thereby reducing manual steps and improving sampling efficiency and detection efficiency.

[0051] Furthermore, the control unit also includes a plurality of first modems and a second modem that cooperates with the first modem electrical signal. The first modem is electrically connected to the first controller, the second controller, the third controller, the fourth controller and the electronic switch valve, and the second modem is electrically connected to the PLC controller.

[0052] Through the above settings, the first modem and the second modem can remotely control the first controller, the second controller, the third controller, the fourth controller and the switch valve, which can further improve the automation of the operation; at the same time, the first modem and the second modem can be many-to-one, and a single PLC controller can control multiple environmental pollution control detection equipment, and can perform sampling and processing at multiple monitoring points at the same time, which can more easily improve the detection and processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 It is an axial schematic diagram of a detection device for environmental pollution control in an embodiment of the present invention.

[0054] Figure 2 for Figure 1 Magnified image of the sampling bottle.

[0055] In the above drawings: mounting frame 10, suction pump 20, first motor 30, drill rod 301, horizontal sliding block 40, groove 401, lifting guide rod 50, support rod 501, guide slider 502, ball screw 601, nut 602, second motor 603, guide rod 604, switch valve 70, sampling bottle 80, first water pipe 801, second water pipe 802. DETAILED DESCRIPTION

[0056] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0057] This embodiment is basically Figure 1 and Figure 2 As shown, an embodiment of the present invention proposes a detection device for environmental pollution control, including a mounting frame 10, a drilling unit, a vertical sliding unit that drives the drilling unit to slide vertically and lock, a horizontal sliding unit that drives the drilling unit to slide horizontally and lock, a suction pump 20, a plurality of sampling units connected to the suction pump 20, and a control unit; the number of mounting frames 10 is two, and the mounting frame 10 is an inverted "T" shape, and bolts that can be pre-installed on the ground are threadedly installed on both sides of the lower end of the mounting frame 10, and the horizontal sliding unit or the vertical sliding unit is installed on the mounting frame 10.

[0058] like Figure 1 As shown, the drilling unit includes a drill rod 301 and a first motor 30 for driving the drill rod 301 to rotate, and the drill rod 301 is vertically arranged; the vertical sliding unit includes a horizontal sliding block 40, four lifting guide rods 50 and a support rod 501, the middle part of the horizontal sliding block 40 is in the shape of a horizontally penetrating groove 401, and a drill hole for the drill rod 301 to pass through is vertically arranged on the horizontal sliding block 40, and the drill hole is located at the center of the groove 401; the lifting guide rod 50 is vertically fixedly installed at four right angles of the groove 401 of the horizontal sliding block 40; at the same time, the support rod 501 is horizontally welded and installed on the lower side of the first motor 30, and a guide slider 502 that can slide vertically along the lifting guide rod 50 is welded on the end of the support rod 501 away from the first motor 30, and a second lead screw cooperating with the guide slider 502 is arranged in the lifting guide rod 50.

[0059] like Figure 1 As shown, the horizontal sliding unit includes a ball screw 601, a nut 602 matched with the ball screw 601, a second motor 603 driving the ball screw 601 to rotate, and a guide rod 604. The ball screw 601 is horizontally rotatably installed between the mounting frames 10; the nut 602 is installed on the horizontal sliding block 40; the second motor 603 is fixedly connected to the mounting frame 10 by bolts; at the same time, the guide rod 604 is arranged parallel to the ball screw 601, and the two ends of the guide rod 604 are fixedly connected to the mounting frame 10 by bolts, and a sliding hole is penetrated on the horizontal sliding block 40, and the sliding hole of the horizontal sliding block 40 is in sliding contact with the guide rod 604.

[0060] like Figure 1 and Figure 2As shown, the suction pump 20 is a double-suction pump, and a switch valve 70 is connected between the plurality of sampling units and the suction pump 20. The sampling unit includes a sampling bottle 80, a first water pipe 801 and a second water pipe 802. One end of the first water pipe 801 is flexible and passes through the borehole, and the other end of the first water pipe 801 is fixedly passed through the horizontal sliding block 40 and can be connected to the sampling bottle 80. The right ends of the first water pipe 801 near the borehole in the plurality of sampling units are different in length, so that water samples of different depths can be sucked; one end of the second water pipe 802 passes through the horizontal sliding block 40 and is connected to the sampling bottle 80. 0 is connected, the other end of the second water pipe 802 is connected to the suction pump 20, the end surface of the first water pipe 801 located at one end in the sampling bottle 80 is lower than the end surface of the second water pipe 802 located at one end in the sampling bottle 80, the cross-sections of the first water pipe 801 and the second water pipe 802 are semicircular, and the cross-sections of the first water pipe 801 and the second water pipe 802 can be assembled into a circle, a single switch valve 70 is installed on the first water pipe 801 and the second water pipe 802 of the same sampling unit, and at the same time, the sampling bottle 80 is threadedly connected to the outer walls of the first water pipe 801 and the second water pipe 802.

[0061] The control unit includes a PLC controller, a first controller for controlling the first motor 30, a second controller for controlling the second motor 603, a third controller for controlling the guide slider 502 to slide along the second lead screw, a fourth controller for controlling the suction pump 20 to be turned on or off, a plurality of first modems and a second modem that cooperates with the electrical signals of the first modems; the switch valves 70 are all electronic switch valves 70, the switch valves 70 are all electronic switch valves 70, the first controller, the second controller, the third controller, the fourth controller and the electronic switch valve 70 are all connected to the PLC controller electrical signals, and the second modem is connected to the PLC controller electrical signals.

[0062] Before using the detection equipment for environmental pollution control in this embodiment, several groundwater monitoring points are selected on the construction site for pre-installation of the detection equipment for environmental pollution control, and the mounting frame 10 is pre-installed to the location to be detected by bolts, so as to realize the fixed-point and long-term installation of the detection equipment for environmental pollution control, and the water quality sampling and detection can be carried out multiple times and for a long time at the monitoring point.

[0063] When performing detection sampling, instructions are input through the PLC controller, and the instructions transmit the control signal to the first modem through the second modem, and then the first controller, the second controller, the third controller and the electronic switch valve 70 are controlled according to the program; when performing the first drilling and sampling, the first controller controls the first motor 30 to start, and the first motor 30 drives the ball screw 601 to rotate, and the ball screw 601 cooperates with the nut 602, the guide rod 604 and the horizontal sliding block 40, so that the rotational force of the ball screw 601 is converted into the power of the horizontal sliding block 40 to move horizontally along the ball screw 601 and the guide rod 604, thereby controlling the horizontal position of the vertical sliding unit, the drilling unit and the sampling unit; when the vertical sliding unit, the drilling unit and the sampling unit move to the controlled position, the first controller controls the first motor 30 to pause, so as to temporarily lock the position of the vertical sliding unit, the drilling unit and the sampling unit.

[0064] Then the second controller controls the second motor 603 to turn on, and the second motor 603 drives the drill rod 301 to rotate, and the third controller synchronously controls the guide slider 502 to move vertically downward along the second lead screw in the lifting guide rod 50, so that the second motor 603 and the drill rod 301 rotate and move downward as a whole, so as to realize the drilling at the monitoring point of the construction site. After the drilling is completed, a sampling hole is formed; then the second controller controls the second motor 603 to turn off, and the third controller synchronously controls the guide slider 502 to move vertically upward along the second lead screw in the lifting guide rod 50 to expose the sampling hole; then the first controller is used again to control the vertical sliding unit, the drilling unit and the sampling unit to move horizontally, so as to facilitate the processing of the next sampling hole.

[0065] When sampling, the end of the first water pipe 801 on the upper left side is embedded in the sampling hole. The depth of the sampling hole is adapted to the sampling depth of the end of the first water pipe 801. When groundwater seeps out of the sampling hole, the fourth controller controls the suction pump 20 to start positive suction, and controls the switch valve 70 on the upper left side to open, and the other switch valves 70 are closed; the suction pump 20 sucks the water in the sampling hole, and the negative pressure is transmitted to the sampling bottle 80 through the second water pipe 802, and the negative pressure of the sampling bottle 80 is transmitted to the first water pipe 802. 01, the first water pipe 801 sucks the water sample in the sampling hole, and the sucked water sample enters the sampling bottle 80 through the first water pipe 801. Since the end surface of the first water pipe 801 at one end in the sampling bottle 80 is lower than the end surface of the second water pipe 802 at one end in the sampling bottle 80, the liquid level of the water sample is maintained at the lower end surface of the second water pipe 802. When the second water pipe 802 is not immersed in the water sample, the corresponding switch valve 70 is closed, and the suction pump 20 can also be directly controlled to pause to stop sampling.

[0066] By repeating the above steps, water samples can be extracted from several sampling holes of different depths in turn. The extraction of each water sample will not interfere with each other, and it is easier to obtain accurate water samples. Water samples at different levels can be collected in an all-round way to know whether the water is polluted, the depth of pollution, the cause of pollution, and other aspects.

[0067] When drilling and sampling, after completing the drilling of several sampling holes in sequence, several first water pipes 801 can be embedded into the corresponding sampling holes, the suction pump 20 can be started, and the switch valves 70 can be opened. The sampling of water samples in multiple deep sampling holes can be completed at one time, and the sampling efficiency is high, which can improve the detection efficiency.

[0068] After the sampling is completed, the sampling bottle 80 on the first water pipe 801 and the second water pipe 802 can be quickly removed by screwing the sampling bottle 80, and the water sample in the sampling bottle 80 can be poured out for testing. The sampling bottle 80 can be easily cleaned and then screwed and installed on the first water pipe 801 and the second water pipe 802. The first water pipe 801 and the second water pipe 802 are tightly matched with the sampling bottle 80 and are easy to assemble and disassemble. It is easy to carry out multiple and long-term water sampling and processing at the monitoring points, and can accurately judge the groundwater quality in the construction environment.

[0069] When treating the water quality in the construction environment, some of the reagents used for treatment can be loaded into the sampling bottle 80. The fourth controller controls the suction pump 20 to start reverse suction, so that the reagents can be transferred to the sampling bottle 80 through the second water pipe 802 by air pressure. The reagents in the sampling bottle 80 can flow back to the sampling holes through the first water pipe 801, thereby realizing the addition of diffusion reagents at the sampling holes of this layer, realizing the treatment of this part of the water environment, and effectively improving the treatment efficiency and accuracy.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A detection device for environmental pollution control, characterized in that: include: Mounting frame; Drilling unit; A horizontal sliding unit that drives the drilling unit to slide horizontally and lock; A vertical sliding unit that drives the drilling unit to slide vertically and lock, wherein the horizontal sliding unit or the vertical sliding unit is installed on a mounting frame; Suction pump; A plurality of sampling units are connected to the suction pump, a switch valve is connected between the plurality of sampling units and the suction pump, and the plurality of sampling units can absorb water samples of different depths.

2. The detection device for environmental pollution control as claimed in claim 1, characterized in that: The drilling unit comprises: Drill pipe; A first motor drives the drill rod to rotate, wherein the first motor is fixedly connected to the vertical sliding unit.

3. The detection device for environmental pollution control as claimed in claim 2, characterized in that: The vertical sliding unit comprises: A horizontal sliding block, wherein the horizontal sliding block is connected to the horizontal sliding unit, and a drill hole for the drill rod to pass through is vertically arranged on the horizontal sliding block; A lifting guide rod, the lifting guide rod is vertically fixedly mounted on the horizontal sliding block; A support rod is horizontally fixedly installed on the lower side of the first motor, and a guide slider which can slide vertically along the lifting guide rod is provided on one end of the support rod away from the first motor.

4. The detection device for environmental pollution control as claimed in claim 3, characterized in that: The horizontal sliding unit comprises: A ball screw, the ball screw is horizontally rotatably mounted between the mounting frames; A nut matched with the ball screw, wherein the nut is mounted on the horizontal sliding block; A second motor driving the ball screw to rotate, wherein the second motor is fixedly connected to the mounting frame; The guide bar is arranged in parallel with the ball screw, and both ends of the guide bar are fixedly connected with the mounting frame. A sliding hole is penetrated on the horizontal sliding block, and the sliding hole of the horizontal sliding block is in sliding contact with the guide bar.

5. The detection device for environmental pollution control as claimed in claim 4, characterized in that: The sampling unit comprises: Sampling bottles; A first water pipe, one end of which is flexible and passes through the drill hole, and the other end of which is fixedly passed through the horizontal sliding block and can be communicated with the sampling bottle; A second water pipe, one end of which passes through the horizontal sliding block and is connected to the sampling bottle, the other end of which is connected to the suction pump, and an end surface of the first water pipe located in the sampling bottle is lower than an end surface of the second water pipe located in the sampling bottle; The switch valve is installed on one end of the first water pipe and the second water pipe close to the bottle mouth.

6. The detection device for environmental pollution control as claimed in claim 5, characterized in that: The cross sections of the first water pipe and the second water pipe are semicircular, and the cross sections of the first water pipe and the second water pipe can be assembled into a circle. A single switch valve is installed on the first water pipe and the second water pipe of the same sampling unit.

7. The detection device for environmental pollution control as claimed in claim 6, characterized in that: The sampling bottle is threadedly connected to the outer walls of the first water pipe and the second water pipe.

8. The detection device for environmental pollution control as claimed in claim 7, characterized in that: The suction pump is a double-suction pump.

9. The detection device for environmental pollution control as claimed in claim 8, characterized in that: Also included is a control unit, the control unit comprising: PLC controller; a first controller for controlling the first motor; a second controller for controlling a second electric motor; A second lead screw matched with the guide slider is arranged inside the lifting guide rod; a third controller for controlling the guide slider to slide along the second lead screw; a fourth controller for controlling the suction pump to be turned on or off; The switch valves are all electronic switch valves, and the first controller, the second controller, the third controller, the fourth controller and the electronic switch valves are all connected to the PLC controller by electrical signals.

10. The detection device for environmental pollution control as claimed in claim 9, characterized in that: The control unit also includes a first modem and a second modem that cooperates with the first modem electrical signal. The first modem is electrically connected to the first controller, the second controller, the third controller, the fourth controller and the electronic switch valve, and the second modem is electrically connected to the PLC controller.

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