41results about How to "Increase the diameter" patented technology

The invention discloses application of a PdAKR2A gene in improving the photosynthetic rate and biomass of poplar, and belongs to the technical field of genetic engineering breeding of poplar. The overexpressed PdAKR2A gene is disclosed for the first time, the cambium cell layer number and xylem width of the poplar can be remarkably increased, the plant height and ground diameter of the poplar are further increased, and therefore the growth rate and biological yield of the poplar are increased; the net photosynthetic rate, stomatal conductance, transpiration rate and chlorophyll content of the poplar can be obviously improved; the lignin and cellulose content of the poplar can be obviously improved; the provided PdAKR2A gene can be used as a candidate gene for cultivating a new variety of poplar which is higher in growth rate and better in quality, and has important significance on promoting sustainable development of forestry in China and relieving supply and demand tension of the wood market.

The invention relates to the technical field of microorganisms, in particular to fusarium and application thereof in promoting blueberry growth. The fusarium is classified and named as Fusarium sp., the strain number of the fusarium is NX1, the fusarium is preserved in the China General Microbiological Culture Collection Center on June 26, 2024, and the preservation number of the fusarium is CGMCC No. 41384. The strain has the capability of obviously promoting the growth of blueberries, and can be cooperated with Alternaria alternata sp.CS9 to further promote the growth of blueberry seedlings, so that an ideal strain resource is provided for developing efficient biological fertilizers or microbial preparations.

The utility model relates to a structure for treating permeation stability of a double-layer embankment foundation, which comprises the embankment foundation, an embankment body is arranged above the embankment foundation, a clay inclined wall is arranged on the upstream side of the embankment body, the bottom of the clay inclined wall is connected with the top of a high-pressure-spraying anti-seepage wall, the bottom of the high-pressure-spraying anti-seepage wall extends into an impervious layer, and the bottom of the high-pressure-spraying anti-seepage wall is connected with the top of the high-pressure-spraying anti-seepage wall. The slope toe of the clay inclined wall is provided with a concrete interlocking block and a grouted rubble foot protection part, the top elevation of the concrete interlocking block protection part is higher than the embankment foot backfill ground line, a geomembrane is arranged at the top of the high-pressure-spraying anti-seepage wall and is laid in the geomembrane tooth groove laying direction, and one end of the geomembrane is fixed in the geomembrane tooth groove fixing direction. The embankment body adopts the clay inclined wall, so that the anti-seepage effect is good, and the embankment foundation deformation adaptability is high. The high-pressure spraying anti-seepage wall is adopted in the embankment foundation, seepage can be effectively blocked, the seepage path can be effectively prolonged, and seepage damage is prevented.

The invention relates to the technical field of electric power construction, in particular to a construction device, construction method and structure of a high-pressure rotary spraying type screw anchor composite foundation, which comprises a high-pressure rotary spraying type screw anchor, a high-pressure grouting system, a power screw-in system and a rotary joint. The situation that a nozzle is blocked is avoided, high-pressure rotary spraying is achieved when the anchor body spirally drills downwards, high-pressure rotary spraying cement slurry is used as a soil improvement means, disturbance related to anchor installation is relieved, the performance of soil in a disturbance area is enhanced, and the diameter of an anchor rod is greatly increased so that the buckling resistance can be improved; and meanwhile, the rotary jet grouting scheme of the large-diameter spiral anchor is considered, and application and popularization of the high-pressure rotary jet type spiral anchor composite foundation can be powerfully promoted.

The utility model belongs to the technical field of water stop structures, and particularly relates to an LUUI closed type rubber water stop belt and a water stop structure used at the joint of a new building and an old building. The water stop belt comprises a double-U-shaped sealing belt, an L-shaped wing plate belt and an I-shaped wing plate belt. The double-U-shaped sealing belt is formed by oppositely buckling two U-shaped belts to form a sealed whole; the L-shaped wing plate belt and the I-shaped wing plate belt are fixed to the two opposite sides of the double-U-shaped closed belt respectively. The water stop structure comprises an L-shaped groove body formed in the side, close to a joint, of an original building, and an L-shaped wing plate strip is matched with the L-shaped groove body and fixed to the L-shaped groove body. The double-U-shaped sealing belt is arranged in a joint of an original building and a new building, and the width B of the double-U-shaped sealing belt is matched with the width of the joint. And the I-shaped wing plate strip is poured in a new building. The LUUI closed type rubber waterstop and the waterstop structure can adapt to telescopic displacement and uneven settlement difference between new and old building concrete, so that the waterstop does not lose efficacy due to overlarge settlement difference and vibration dislocation, and potential safety hazards caused by premature tearing failure are avoided.

In the catheter, the shaft includes a wire lumen; a sensor lumen that is arranged side by side with the wire lumen; a projection part that includes the wire lumen, projects to the more distal side than the distal end of the sensor lumen, and has a distal end opening communicated to the wire lumen at the distal end of the projection part; and a first notch that is a notch formed on the more proximal end side than the projection part, and is communicated to the wire lumen. The first notch is formed on a side surface of the shaft, the side surface being positioned on the opposite side of the sensor lumen with a center axis of the wire lumen as a reference, and the shaft includes, in a section with the first notch, a bottom portion facing the first notch and a pair of side walls extending to the opposite side of the sensor lumen.

The present application provides a wet method flower basket, which belongs to the field of solar cell production equipment. A wet method flower basket includes a first support plate, a second support plate and a plurality of flower basket rods arranged between the first support plate and the second support plate. A plurality of flower basket rods enclose a receiving cavity for accommodating silicon wafers, and the receiving cavity has a receiving opening for silicon wafers to enter and exit the receiving cavity. Each flower basket rod is provided with a plurality of flower basket teeth spaced axially on one side facing the receiving cavity, and any two adjacent flower basket teeth of each flower basket rod have a receiving groove for accommodating the edge of the silicon wafer, and the receiving grooves between the flower basket rods are arranged correspondingly. Another wet method flower basket includes a first support plate, a second support plate and a plurality of flower basket rods arranged between the first support plate and the second support plate. A plurality of flower basket rods enclose a receiving cavity for accommodating silicon wafers, and the receiving cavity has a receiving opening for silicon wafers to enter and exit the receiving cavity. The flower basket rod is a carbon fiber rod, with a circular cross section and a diameter of 15-25 mm. It can effectively reduce the occurrence of basket floating phenomenon and silicon wafer displacement phenomenon.

The present invention provides an intercropping method for improving the growth rate of young white agarwood, comprising the following steps: (1) transplanting white agarwood seedlings, and intercropping okra after the white agarwood is planted; (2) fertilizing: before the white agarwood is planted, nitrogen, phosphorus and potassium compound fertilizer is applied as base fertilizer, and after the planting, nitrogen, phosphorus and potassium compound fertilizer is applied every year after weeding and loosening the soil; nitrogen, phosphorus and potassium compound fertilizer and calcium magnesium phosphate fertilizer are applied as base fertilizer for okra; (3) inter-cultivation and weeding; (4) pest control; (5) after the okra is harvested, the discarded stems and leaves are collected, the stems and leaves are piled in the forest, and the stems and leaves of the okra are fermented and rotted and applied around the roots of the white agarwood. The present invention intercrops okra one month after the white agarwood seedlings are planted. Compared with other intercropping patterns, intercropping okra can significantly increase the ground diameter, tree height and crown width, and can significantly increase the growth rate of young white agarwood.

This rotating electric machine comprises: a stator having a stator core around which a plurality of coils are wound; a rotor supported to be rotatable relative to the stator with a predetermined gap therebetween; a rotor case that holds the rotor; and a first bearing (201) and a second bearing (202) that rotatably support the rotor case. The rotating electric machine includes: a first flow path formation body (501) that forms a first flow path (501s) through which a refrigerant flows to a coil end part (601) protruding from the stator core; a first case part (401) which forms an accommodation space (201s) of the first bearing, is connected to the first flow path of the first flow path formation body, and fills the accommodation space with the refrigerant; a second flow path formation body (502) which forms a second flow path (502s) through which the refrigerant flows to a coil end part (602) disposed on the opposite side from the coil end part in the axial direction; and a second case part (402) which forms an accommodation space (202s) of the second bearing, is connected to the second flow path of the second flow path formation body, and fills the accommodation space with the refrigerant.

A cylindrical lithium primary battery of the present application includes an electrode body that is configured such that a positive electrode and a negative electrode are spirally wound with a separator interposed therebetween. The positive electrode includes a positive electrode current collector and positive electrode mixture layers that are disposed on both surfaces of the positive electrode current collector and contain manganese dioxide as a positive electrode active material. The manganese dioxide content per unit area of each of the positive electrode mixture layers is 0.205 to 0.227 g / cm2 for one surface of the positive electrode current collector. The negative electrode includes a negative electrode current collector and two lithium layers that are disposed on one surface of the negative electrode current collector and spaced 6 to 12 mm apart in the longitudinal direction. Each of the two lithium layers has a lithium content of 0.014 to 0.017 g / cm2 per unit area. The negative electrode is wound in such a manner that the negative electrode is folded back so that the folded negative electrode current collector overlaps itself, and the inner peripheral ends of the two lithium layers are respectively located outside the winding center.

The embodiment of the invention provides a hair dryer. The hair dryer comprises a shell and a motor, the fan is arranged in the air duct; the connecting piece is connected with the shell, and a ventilation opening is formed in the connecting piece and communicated with the air duct; the heating piece is arranged in the air duct and located between the fan and the connecting piece; a medicament containing cavity is formed in the medicament bin, a medicament volatilization hole communicated with the medicament containing cavity is formed in the medicament bin, and the medicament bin is detachably connected with the connecting piece; an air outlet hole channel is formed in the air outlet piece, the air outlet piece is detachably connected with the connecting piece, and the medicament bin can be clamped between the connecting piece and the air outlet piece; and the ventilation opening, the medicament volatilization hole and the air outlet hole channel are communicated with one another. The hair dryer can spray the gaseous hair care essential oil to the hair of a user, the mode that the user smears the hair care essential oil with the hand is replaced, and the problem that the hair care essential oil is left on the hand of the user is solved; moreover, the hair care essential oil is volatilized into gas, so that the hair care essential oil can be fully absorbed by the hair of the user.

The invention discloses a molten salt storage tank, a molten salt energy storage system and a temperature control method thereof. The molten salt storage tank comprises a shell, a heat insulation layer arranged in the shell and a temperature control layer arranged outside the shell; the heat insulation layer comprises a first heat insulation layer arranged on the inner side of the shell and a second heat insulation layer arranged on the inner bottom of the shell, and the temperature control layer comprises a first temperature control layer arranged on the outer side of the shell and a second temperature control layer arranged on the bottom of the second heat insulation layer; the invention arranges a heat insulation layer inside the shell and a temperature control layer outside the shell, and controls at least part of the molten salt in the gap between the first heat insulation layer and the second heat insulation layer to solidify by adjusting the thickness of the heat insulation layer on the side, the wind speed of the first ventilation channel layer and the wind speed of the second ventilation channel layer, thereby playing a role of sealing the heat insulation layer, so that the molten salt will no longer flow to the outside, and thus the molten salt will not corrode the shell.

The invention discloses a preparation method of temperature-adjusting Lyocell fibers loaded with phase change microcapsules, and belongs to the technical field of phase change materials. The method comprises the following steps: 1) reacting SMA with a sodium hydroxide solution, and adjusting the pH value with a citric acid solution to obtain an emulsifier, wherein the SMA accounts for 4-6% of the total mass of the emulsifier; carrying out high-speed shearing emulsification on an emulsifier and n-octadecane for 20-40 minutes to form an oil-in-water emulsion, dropwise adding the melamino-formaldehyde prepolymer under mechanical stirring, and reacting to obtain a phase change microcapsule; and 2) uniformly dispersing the phase change microcapsules into 45-55wt% of an NMMO aqueous solution, then removing water to increase the concentration of the NMMO to 80-90%, then sequentially adding propyl gallate and wood pulp powder, and after the wood pulp powder is completely dissolved, carrying out wet spinning to obtain the phase change microcapsule loaded temperature-regulating Lyocell fiber. The obtained fiber is small in diameter, has high enthalpy heat and good temperature adjusting capability, and is wide in application prospect.

The invention relates to a prefabricated field water recession channel component which is formed by splicing a plurality of component bodies, each component body comprises a side wall and a blocking piece, the side wall comprises a bottom plate, a first side plate and a second side plate, and the first side plate and the second side plate are located on the two opposite sides of the bottom plate; the first side plate and the second side plate have preset heights; the blocking piece is arranged at the top of the bottom plate and comprises a longitudinal partition plate and a transverse baffle, the length direction of the longitudinal partition plate extends in the width direction of the bottom plate, the longitudinal partition plate is close to the first side plate, the length direction of the transverse baffle extends in the length direction of the bottom plate, and the transverse baffle is connected with the second side plate and the longitudinal partition plate; the multiple component bodies have a splicing state, and in the splicing state, the first side plate of one component body is adjacent to the second side plate of the other component body. The prefabricated field water recession channel component can reduce the land occupation in the field, can prolong the seepage path and slow down the flow velocity, and is more convenient to construct.

Nucleotide sequences including a micro-dystrophin gene are provided. The micro-dystrophin genes may be operatively linked to a regulatory cassette. Methods of treating a subject having, or at risk of developing, muscular dystrophy, sarcopenia, heart disease, or cachexia are also provided. The methods may include administering a pharmaceutical composition including the micro-dystrophin gene and a delivery vehicle to a subject. Further, the methods may include administering the pharmaceutical composition a subject having Duchenne muscular dystrophy or Becker muscular dystrophy.

The present invention provides a stone removal device and a method for using the same, and belongs to the technical field of medical devices. The stone removal device includes an optical fiber, a basket structure, and a limiting assembly. The optical fiber is used to transmit laser light. The basket structure includes a plurality of basket connecting wires arranged around the optical fiber, and the proximal ends of all the basket connecting wires are fixed to the optical fiber, and the distal ends of all the basket connecting wires are connected to each other to form a basket body on the distal side of the optical fiber. The limiting assembly includes a limiting structure and a control member. The limiting structure is sleeved outside the optical fiber, the limiting structure is located on the proximal side of the basket body, the distal end of the control member is connected to the limiting structure, and the proximal end of the control member extends toward the proximal end of the optical fiber. The control member is used to control the expansion or retraction of the limiting structure on the optical fiber to increase or decrease the diameter of the limiting structure. The present application fixes the optical fiber to the instrument channel of the insertion part by setting a limiting structure, stabilizes the position of the optical fiber in the instrument channel, and improves the coaxiality of the optical fiber and the instrument channel.

A flow control valve, comprising: a valve body (21), the valve body (21) having a valve seat part (211) provided therein, with a valve port (112) formed in the valve seat part (211); a spool (12), the spool (12) being axially movable to open or close the valve port (112), with a pressure-equalizing channel (121) provided in the spool (12), the pressure-equalizing channel connecting the valve port (112) and a back-pressure chamber (14), wherein the spool (12) has a substantially cylindrical lower end (222), and a conical hole (223) is formed in the spool (12), the conical hole (223) forming part of the pressure-equalizing channel (121), a bottom end of the conical hole (223) being located on a bottom plane (224) of the lower end (222), and the ratio of the diameter of the bottom end of the conical hole (223) to the diameter of the lower end (222) being greater than 0.88. In the present application, the conical hole (223) is provided on the spool (12) of the flow control valve, the conical hole (223) forming part of the pressure-equalizing channel (121), with the bottom end of the conical hole (223) being located on the bottom plane (224) of the lower end (222) of the spool (12). The conical hole (223) is dimensioned so that the pressure distributed at a lower part of the spool (12) becomes uniform, so as to balance fluid pressures in the back-pressure chamber (14) and the valve port (112).

The invention belongs to the field of optical communication transmission, and particularly discloses a high-tensile-strength framework type ribbon optical cable and a preparation method thereof.The high-tensile-strength framework type ribbon optical cable comprises a framework type cable core and a sheath body, the sheath body wraps and is attached to the outer portion of the framework type cable core, and the framework type cable core comprises a framework body and a plurality of optical fiber ribbons; a plurality of skeleton grooves are formed in the peripheral side of the skeleton main body; the plurality of optical fiber ribbons are respectively arranged in the corresponding skeleton grooves; the skeleton-type cable core also comprises a water-blocking tape, and the water-blocking tape wraps the optical fiber tape and the skeleton main body. The sheath body comprises an inner sheath layer, a tension enhancement layer and an outer sheath layer which are sequentially arranged from inside to outside. According to the skeleton-type ribbon optical cable, the sheath body is combined with the skeleton-type cable core, so that the whole optical cable has better tensile performance on the premise that the advantages of high optical fiber density, small diameter and weight, no pollution and the like of the existing skeleton-type ribbon optical cable are reserved, and the skeleton-type ribbon optical cable is suitable for use and construction occasions with higher requirements on the tensile force of the optical cable.

The utility model provides a kind of building insulation board joint sealing device, it is related to insulation board installation technical field, and it includes: glue injection mechanism, the glue injection mechanism includes filling cylinder, one end of the filling cylinder is equipped with connecting barrel, the inside of filling cylinder is sleeved with glue injection pipe, the glue injection pipe is fixedly connected with filling cylinder, the outer surface of the glue injection pipe is sleeved with connecting frame, the connecting frame is fixedly connected with glue injection pipe, the side surface of the connecting frame is fixedly connected with support rod.The utility model, by being provided with glue injection mechanism, the sealant that fills the gap between insulation board is effectively filled into the inside of gap, so that the heat preservation effect when using insulation board is better, and glue injection pipe is set, and the diameter of glue injection pipe is smaller, and then glue injection pipe can be deeply filled into the gap between insulation board, so that sealant can be filled into the inside of gap.

The utility model discloses a kind of axle gear lubrication structures, including input shaft and gear installed on input shaft, the oil hole is opened in the input shaft, and lubricating oil is sent into the raceway surface of input shaft and gear mounting cooperation by oil hole, the raceway surface of input shaft is opened with several lubricating grooves, synchronizer gear sleeve is equipped on the input shaft, and synchronizer gear sleeve fixes input shaft and gear to realize power output.The utility model cancels the needle roller bearing arranged between input shaft and gear, saves space and increases the diameter of input shaft and gear, improves the strength and stiffness of axle and carrying capacity, avoids the phenomenon that gear or input shaft appears fracture;Replace needle roller bearing in prior art by lubricating groove, not only eliminate the risk of needle failure, while reducing production cost.

This utility model discloses a subsea pipeline inspection robot for marine engineering, relating to the field of marine engineering technology. It includes a walking frame with two sets of drive wheels mounted on both sides of the frame, each driven by an independent synchronous motor. A stabilizing mechanism is installed inside the drive wheels. Adjustable panoramic cameras are located at the front and rear ends of the walking frame. A movable groove is located in the middle of the walking frame, and a movable ring is mounted on the outside of the groove via bearings. An all-around inspection mechanism is located outside the movable ring. The all-around inspection mechanism includes a drive motor and spherical cameras. Multiple sets of spherical cameras are arranged in a ring outside the movable ring. A drive motor is located above the movable groove on the outside of the walking frame, driving the movable ring to rotate and performing precise inspections through the spherical cameras. This utility model significantly improves the adaptability and work efficiency of the inspection robot by enhancing its imaging capabilities and innovating its walking drive structure.

The invention relates to the technical field of microorganisms, in particular to rhizosphere Cupriavidus sp. 10 and application thereof in the aspects of phosphorus solubilization and growth promotion. The preservation number of the rhizosphere Cupriavidus sp. 10 provided by the invention is GDMCC No.65501. The rhizosphere Cupriavidus sp. 10 can improve the content of chlorophyll a, chlorophyll b, carotenoid and total chlorophyll in the leaves of the seedlings of amur corktree, and increase the plant height, ground diameter, total fresh weight, fresh root weight, fresh stem weight, fresh leaf weight, total root length and number of thick roots of the seedlings of amur corktree. Meanwhile, accumulation of soluble sugar and available phosphorus in roots and leaves is promoted.

The present invention provides a treatment method for improving the effect of synchronized estrus-timed insemination of buffaloes in summer. The treatment method is to inject melatonin into the multiparous buffaloes two days before the synchronized estrus treatment, i.e., on the 48th day after delivery, and then perform sympathetic estrus-timed insemination. The present invention also provides a new use of melatonin. The treatment method of the present invention effectively improves the synchronized estrus rate of multiparous milk buffaloes in summer, promotes follicle development and development speed, breeding rate and conception rate, and can increase the milk production and early embryo survival rate of buffaloes, reduce the somatic cell count, and does not require estrus detection, and synchronized insemination is convenient to operate.

An acoustic transducer includes a housing, a diaphragm, a support plate, a motor and a drop ring. The motor includes a back plate, a front plate, a magnet and a voice coil. The drop ring connects the diaphragm to the drop ring at the periphery of the drop ring. The drop ring extends parallel to the central axis of the housing. The periphery of the support plate is spaced from the motor and connected to the diaphragm at the resonance node of the diaphragm.

Intraocular lenses for reducing Negative dysphotopsia (ND) are described herein. An example ophthalmic lens can include an optic with a central optical zone disposed about the optical axis and an attenuation optical zone disposed about the central optical zone, wherein the attenuation optical zone is contiguous with the central optical zone, and wherein optical power of the ophthalmic lens is gradually reduced within the attenuation optical zone.

The application discloses a layered sand prevention and polymer injection integrated pipe column and a construction method, relates to the technical field of oil exploitation, and the pipe column comprises a downhole pipe column and a control pipe column. The downhole pipe column comprises a layered sand prevention and polymer injection unit. The layered sand prevention and polymer injection unit comprises a positioning cylinder, an adjustable sand prevention and injection device, a blockage removal injection device and layered packers. The control pipe column comprises a positioning tool and a repeatedly switchable tool. The positioning tool can be positioned with the positioning cylinder, and the repeatedly switchable tool can control and regulate the adjustable sand prevention and injection device and the blockage removal injection device. The application realizes sand prevention and polymer injection integration through the adjustable sand prevention and injection device. The application realizes downhole efficient regulation through the positioning tool and the repeatedly switchable tool.

A wide-angle lens which easily and appropriately corrects various aberrations such as field curvature, magnification chromatic aberration, and coma aberration, and easily achieves miniaturization of the entire wide-angle lens. The wide-angle lens of the present invention includes, in order from the object side, a first lens which is a negative lens with a concave image side lens surface, a second lens which is a negative lens with a concave image side lens surface, a third lens which is a positive lens with a convex image side lens surface, a fourth lens which is a positive lens with a convex image side lens surface, a fifth lens which is a positive lens, a sixth lens which is a negative lens, and a seventh lens which is a positive lens, and satisfies the following relationship when a focal length of the third lens is set as f3 and a focal length of the entire wide-angle lens is set as f: 3.000 < f3 / f < 12.500.

The invention discloses laser cutting equipment for pipes, and aims to provide a pipe cutting machine with an anti-blocking discharging structure and a machining method of the pipe cutting machine with the anti-blocking discharging structure, and the pipe cutting machine with the anti-blocking discharging structure and the machining method of the pipe cutting machine with the anti-blocking discharging structure can prevent pipe fittings from being damaged in the discharging process, can guarantee orderly stacking of the pipe fittings after discharging is completed and can reduce the working intensity of workers. According to the technical scheme, a guide mechanism capable of enabling the pipe fittings to slide down along a fixed track is additionally arranged at a discharging structure, the guide mechanism can receive the pipe fittings machined from a machining table, the moving paths of the pipe fittings are limited through clamping grooves, the pipe fittings can be disengaged from the clamping grooves in a fixed direction, and therefore the pipe fittings can be separated from the clamping grooves in the fixed direction. The clamping groove for conveying the pipe fittings is of a gradually-shrinking structure, so that the pipe fittings can be accurately received and stably slide along a set path, mutual collision caused by free falling of the pipe fittings is avoided, the rate of finished products is increased, the labor intensity of operators is reduced, the production efficiency and the automation level are remarkably improved, and the production cost is reduced. The method is suitable for the technical field of pipe fitting machining.

The utility model relates to sensor technical field, specifically disclose a kind of multi-axis force sensor, including elastomer and cover body, elastomer includes first shell, second shell, T type beam, first cabin, second cabin, first cabin is provided with first circuit board in, second cabin is provided with group bridge circuit board, first cabin and second cabin are used to expand the internal space of elastomer whole, to be able to place multiple circuit boards and electrical components to increase functionality, cover body is filled with elastic sealant between first shell, still separately set up the glue groove for filling sealant, to further improve the sealing level of sensor, by integrating group bridge piece on group bridge circuit board, and setting zero part at the accommodation slot, both can be easily factory debugging also can be easily repair dismantling strain gauge, without dismantling internal electrical components, so that it has convenience of debugging and maintenance.

Intraocular lenses for reducing Negative dysphotopsia (ND) are described herein. An example ophthalmic lens can include an optic with a central optical zone disposed about the optical axis and an attenuation optical zone disposed about the central optical zone, wherein the attenuation optical zone is contiguous with the central optical zone, and wherein optical power of the ophthalmic lens is gradually reduced within the attenuation optical zone.