diff --git a/Modbus.Net/Modbus.Net.Standard/Modbus.Net.Standard.csproj b/Modbus.Net/Modbus.Net.Standard/Modbus.Net.Standard.csproj
index 6561935..1f55f26 100644
--- a/Modbus.Net/Modbus.Net.Standard/Modbus.Net.Standard.csproj
+++ b/Modbus.Net/Modbus.Net.Standard/Modbus.Net.Standard.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netstandard1.5</TargetFramework>
+    <TargetFramework>netstandard1.3</TargetFramework>
     <AssemblyName>Modbus.Net</AssemblyName>
     <RootNamespace>Modbus.Net</RootNamespace>
     <PackageId>Modbus.Net</PackageId>
diff --git a/Modbus.Net/src/Base.Common/BaseProtocal.cs b/Modbus.Net/src/Base.Common/BaseProtocal.cs
index 29b9ad4..53816a6 100644
--- a/Modbus.Net/src/Base.Common/BaseProtocal.cs
+++ b/Modbus.Net/src/Base.Common/BaseProtocal.cs
@@ -47,7 +47,7 @@ namespace Modbus.Net
                 }
                 //自动寻找存在的协议并将其加载
                 var protocalUnit =
-                    Assembly.Load(type.GetTypeInfo().Assembly.GetName()).CreateInstance(protocalName) as ProtocalUnit;                
+                    Activator.CreateInstance(type.GetTypeInfo().Assembly.GetType(protocalName)) as ProtocalUnit;              
                 if (protocalUnit == null) throw new InvalidCastException("没有相应的协议内容");
                 protocalUnit.Endian = Endian;
                 Register(protocalUnit);
diff --git a/Modbus.Net/src/Base.Common/ProtocalLinker.cs b/Modbus.Net/src/Base.Common/ProtocalLinker.cs
index e2eaf34..5a244b0 100644
--- a/Modbus.Net/src/Base.Common/ProtocalLinker.cs
+++ b/Modbus.Net/src/Base.Common/ProtocalLinker.cs
@@ -1,4 +1,5 @@
-using System.Reflection;
+using System;
+using System.Reflection;
 using System.Threading.Tasks;
 
 namespace Modbus.Net
@@ -112,7 +113,7 @@ namespace Modbus.Net
         {
             //自动查找相应的协议放缩类，命令规则为——当前的实际类名（注意是继承后的）+"BytesExtend"。
             var bytesExtend =
-                Assembly.Load(GetType().GetTypeInfo().Assembly.GetName()).CreateInstance(GetType().FullName + "BytesExtend") as
+                Activator.CreateInstance(GetType().GetTypeInfo().Assembly.GetType(GetType().FullName + "BytesExtend")) as
                     IProtocalLinkerBytesExtend;
             return bytesExtend?.BytesExtend(content);
         }
@@ -126,7 +127,7 @@ namespace Modbus.Net
         {
             //自动查找相应的协议放缩类，命令规则为——当前的实际类名（注意是继承后的）+"BytesExtend"。
             var bytesExtend =
-                Assembly.Load(GetType().GetTypeInfo().Assembly.GetName()).CreateInstance(GetType().FullName + "BytesExtend") as
+                Activator.CreateInstance(GetType().GetTypeInfo().Assembly.GetType(GetType().FullName + "BytesExtend")) as
                     IProtocalLinkerBytesExtend;
             return bytesExtend?.BytesDecact(content);
         }
diff --git a/Modbus.Net/src/Base.Common/TaskManager.cs b/Modbus.Net/src/Base.Common/TaskManager.cs
index 0c3fcb1..245c661 100644
--- a/Modbus.Net/src/Base.Common/TaskManager.cs
+++ b/Modbus.Net/src/Base.Common/TaskManager.cs
@@ -116,7 +116,7 @@ namespace Modbus.Net
         /// </summary>
         private void NotifyThreadPoolOfPendingWork()
         {
-#if NET45
+#if NET40 || NET45 || NET451 || NET452 || NET46 || NET461 || NET462
             ThreadPool.UnsafeQueueUserWorkItem(_ =>
 #else
             ThreadPool.QueueUserWorkItem(_ =>
diff --git a/README.md b/README.md
index ea699de..bb143b8 100644
--- a/README.md
+++ b/README.md
@@ -20,8 +20,8 @@ There are also "Modbus.Net.Siemens" that can communicate to Siemens S7-200, S7-2
 Platform Supported
 -------------------
 * Visual Studio 2017
-* .Net Framework 4.5
-* .Net Standard 1.5
+* .NET Framework 4.5
+* .NET Standard 1.3
 
 ##RoadMap